The problem is that when the older generation dies out, the younger generation is no longer young, and their attitudes have changed. Not quite to the same exact conservative/anti-progressive place that their parents and grandparents occupied, but definitely more conservative than they were when they were younger.
We'll see progress, to be sure (and that's good!), but it won't be as dramatic as you think. It'll likely be similar to the last several generations of progress.
That's true to an extent, but I think this time is different because the millenials have had to endure so much obvious hardships as a direct result of the baby boomers' incompetence (eg. student debt), and because millennials grew up with the internet and all the information that gives one access to. Politicians like Bernie and AOC are more in line with how millennial stand (my Boomer dad doesn't understand what they're so angry about), and if those policies were implemented, that'd be a massively different society than today.
We'll see progress, to be sure (and that's good!), but it won't be as dramatic as you think. It'll likely be similar to the last several generations of progress.