To me PE is just secondary effect of incentivizing private pension schemes over pay-as-you-go schemes in the last half century to me.
A huge wealth transfer in disguise providing capital to financial actors (not at last PE) that are usually not aligned with goals of regular employess: affordable housing and healtcare and reasonably safe jobs.
As Germany is on it's way to dismantle it's core of it's pay-as-you-go mandatory state pension insurance and shift towards private, and privat-by-proxy schemes via company pension plans. Europe might be also going that way some time in the near future, but without the comparably healthy demographics of the US.
https://en.wikipedia.org/wiki/Revenue_Act_of_1978
Funny that all those charts eventually go back to Carter allowing for 401k not, Reagan, though that reuse only happened later.
My bigger hunch here is supplying the capital markets with that much additional money was a mistake, that ultimately lead to the current guilded age and accelarated existing trends of in the productivity–pay gap, social stratification and wealth inequality, if not solely being responsible for it.
It seems outright impossible for most to compete with a economic reality where the accrued value of like a third of your and everyone else's paycheck is actively working against your net quality of living, when you're not in the top 1 to 10% where the capital gains are a still a net positive over the increased cost of housing and wage stagflation etc.