I understand your frustration but i think in order to solve the issue I think we need to first identify the true culprit of what's causing life to be so expensive that millennial and the generations younger than that are starting to look favorably at socialism.
The short answer for who is primarily blame is "the government".
Look, I'm 38 years old which makes me as old as you can be and still be a millennial. There is no doubt in my mind that you are correct when you say a large percentage millennial's are self entitled and way too into material goods. How did they get that way? Firstly it's proper to blame the parents because kids don't come out entitled and irresponsible that is a learned skill. But the sheer number suggests the problem is bigger than a crazy amount of bad Baby Boomer / Old Gen X parents.
Let's look at the two things that Millennial complain about the most when it comes to expenses. Education and Housing (Most are two young to care about healthcare yet).
For Education, I can tell you that I grew up being constantly told in every school I went too that if I wanted to get a good job, I had to go to college.
The way the Government "helped" was by putting a guarantee on student loans making a risk free endeavor for companies to give out loans to kids. These government backed loans by the way cannot be forgiven by bankruptcy like you can with other forms of debt.
So why is this a problem? Supply and demand. If you artificially increase the demand for a product (college) the supply will either grow (if it can) or get more expensive to reach equilibrium.
I went to a state school and transferred to a more prestigious university for the last two years. I had to take student loans out to pay for it but was working at the time so i was able to cover my living expenses and only took the loans for tuition. When i was done with my two years, i had about 55,000 dollars in debt. This was in 2004. 15 years later, Tuition for that same school is 47,470, nearly double of what i paid.
That isn't the worst part though. The "everyone" should go to college push by the government, means that you have huge increase in the supply of college graduates. And when you have a huge supply of something, prices inevitably go down for that thing. So now you have a huge population of young people who have paid 2-3 times as much for an education as gen X did and at the same time there is so many of them with the degree that there is no exclusivity to have the degree. This is why you get people with degrees working at Starbucks.
And this is why many of them are entitled. They were told all their life that if you do good at school and get into college you will get a good job. Well there isn't an infinite number of "good" jobs and you need to motivated, hardworking and smart to get them. What's worse is many schools have significantly lowered their standards to get in on the government subsidized gravy train. So they lower the bar and raise the price.
What does this mean? It means that you have a large number of college graduates who aren't smart or motivated enough to get the best jobs, but they feel like they are "too good" for many vocational jobs (That pay good money) because those were frowned upon in school (again government). So not only are they not getting the good jobs, but they are saddled with a 100k or more in debt. When that much of your income is going to pay for a overpriced education, you are going to have a hard time buying a house.
Speaking of housing, that is the second thing the government has really screwed the pooch. For all of my life, housing prices have been on a steady increase, greatly outpacing inflation. Even with the great recession housing prices here in California now exceed the the amounts that existed at the height of the stupidness before the recession hit. Why have they increased this much? Again, it's government manipulation of the market. They have kept interest rates artificially low, while creating programs to make it easier for less qualified people to buy a house.
On the surface, that seems like a good thing. Why wouldn't we want more people to be able to get loans for a house? Again the answer is supply and demand, and it doesn't care about your good intentions. If you increase the demand, and then you say put regulations in place that make building new homes harder or more expensive (California is particularly bad at this) then the only thing that can happen is prices go up.
If you are a Boomer or Gen X this helps you because the house you bought is going up and you can eventually cash out on that equity and use it for anything you like. But it's screwing the person who is looking to buy their first home. When my wife and I bought our place, it was 2011 and was the "bottom" of the market. We looked at a condo in a far suburb of LA that was reasonably close to my work and we paid over 400k for a "steal". It ended up being a good investment when we sold it but that's still a lot of money.
When we looked at house with a yard, we looked at some of the older neighborhoods that had been traditionally standard middle class. The houses were between 1400 - 2000 square ft and had a yards that were between a 1/10th of an acre and a 1/4 acre. Most of the house were 30-40 years old and were selling for 700k!
Luckily at that point we were in a position where we could leave LA and still work and moved to a smaller town where the housing was comparatively reasonable.
But how many people can work remote? Even if the "good jobs" are available in places like this, what does it matter if such a giant chunk of your income goes to housing? I always heard that you shouldn't be buying a house that exceeded three times your gross salary or else you would be spending too much on that house. That means you would need to make over 230,000 a year to be able to "afford" what was in the 60's a starter house. Also, you need to save up 140,000 to get the traditional 20% down that used to be the requirement.
Imagine having to pay 3x what you did for your house when you were starting out. You might say yes but inflation has also happened so that even though you paid less the dollar was worth more. That's true, but if you look at average wages in the US, they have stayed pretty much consistent when you adjust for inflation (https://www.pewresearch.org/fact-tank/2018/08/07/for-most-us-workers-real-wages-have-barely-budged-for-decades/). Housing has greatly outpaced inflation, meaning that people are paying more even in adjusted terms than they were.
I know this is a long winded response but i wanted to bring this up because I find that engaging in these generation wars is a great way to distract us and be able to unite against what's actually causing this. And the cause is our government's reckless policies. I'm not even going to touch the national debt here.
So while nothing pisses me off more than entitled social justice warrior, I do think it some of the grievances they are talking about are legitimate, like the two i just outlined.
We need more millenial's to be prepared if we are to mitigate the negative impact to this country considering the economic challenges that face us. Once you become prepared you tend to spend less on the frivolous anyhow.
But the way to achieve this isn't to perpetuate a generation war. The millenials have legitimate flaws and also legitimate grievances. If we want to move them away from socialism, which will be a huge bloody disaster as history has shown, we need to acknowledge where they have a right to be pissed and point them to the true culprit.... our Government.
It's hard to advocate for more government (socialism) when you are eyes are opened to the fact that they caused the mess we are in.