I'm not sure why a back redistribution of wealth between Boomers and their children does not happen.

In Russia you would be set for an absolute boomer domination, since they could privatize the apartments they rented from state after 1991 (virtually for free), and keep them, but their children would get nothing and will have to rent. But in fact that does not happen because as boomers die off, their grandchildren get apartments inherited by their parents. Not by any law but by intra-family wealth redistribution.

Maybe US & UK Boomers were the exception in that they lived in economic environment where they could earn such wealth from scratch, so they are just not ready to share?