I agree that the college system is messed up. I think it's largely because of the government's push to make it accessible to everyone, even if it's not a good fit for them. Non-dischargeability was arguably part of that - it makes it so that people who wouldn't otherwise be able to get loans have that option, and for everyone else, the interest rate is lower than it might otherwise be. But I think non-dischargeability was a bad idea, on the balance.
Your other complaints I think are mostly just part of the current economic reality of the world - low interest rates and relative economic stability have driven up asset prices to extreme levels, including housing. It's also the main reason for the ever-present inequality headlines. "Stock market continues to do really well, saving otherwise screwed pension plans" doesn't generate the same number of rage clicks, though. Free trade, improved telecommunications, and very efficient container shipping have made it so that you're now competing much more directly with hundreds of millions of well educated Chinese and Indian workers, or billions of less educated Indians and Chinese, depending on your profession, which has increased available labor supply, and decreased worker negotiating power. Contrast this with the boomers, who were born into a country with one of the very few strong, unscathed industrial bases, which helped rebuild the world. Of course they had an easier time economically. But time marches on. Maybe you can blame them for not managing the wealth better.
Which brings me to my next point - it's not that Millenials are dumb with money, most Americans of all ages who didn't experience the Great Depression are.
You say that the amount extra they could be saving is a drop in the bucket, but the difference between saving -$50/mo and +$50/mo is only $100, but it's also the difference between a debt spiral and building up an emergency fund. And that's only going out a few times (or less than once in a HCOL city), or cutting cable. And then saving another $100/mo literally triples that savings rate. Many Americans are around that level of personal profitability, so it's worth talking about.
I think a deep depression is coming in the next credit/debt cycle bust or the one after, based on what I've been reading about how debt cycles work (I recommend Big Debt Crises by Ray Dalio), which should bring asset prices down. Of course, it'll also bring incomes down, spike unemployment, and a whole host of other shitty problems.
I agree that saving more isn't a cure-all, but it's pretty powerful. We should absolutely try to change some things about the world - I'm a monthly donor to Bernie and some other causes, and I go to city council meetings to argue against homeowner associations to try to overturning restrictive zoning rules to get more dense housing supply online and bring down rents. But in the meantime, being more frugal would absolutely help most people. Part of that is that it would give them much more financial freedom and confidence to demand higher wages with the knowledge that they could afford to lose their current job if it came to that. It might make them focus less on how they feel victimized by the world, which may help them avoid becoming depressed. And decreasing consumption would make their lifestyle more environmentally sustainable. And they might find that they just don't need much in the way of material goods to be happy, which is an incredibly freeing discovery. We could all benefit from being a bit more frugal. But part of that is accepting that you're largely responsible for the outcome of your life (modulo your starting conditions) and going against the grain a bit to work towards making it better.
I know that some people cannot save anything, because they're working multiple jobs, supporting kids, and still have to scrimp just to make ends meet. But I'm pretty sure they're not the ones complaining on the internet.