How much is the rise of finance capitalism the result of an ageing society?

Seen a lot of videos on my feed from broadly Kensyian perspectives that run like this:

– Boomers had it good because in the past (1950s-1970s) a person with no higher education could get a secure job, buy a house and provide a comfortable standard of living for themselves and their family.

– This worked because back then companies invested surplus profits in higher wages, capital improvements and R&D (Good capitalism)

– Then came the rise of finance capital and surplus profits started being extracted to enrich greedy hedge fund managers, making things worse for everyone else. (Bad capitalism)

This is an appealing narrative, in part because it offers a solution (albeit a difficult one) to return to a broadly desirable vision of society. One thing however that bothers me is that these videos never seem to mention the role of pensions. I am no economist, but know pension funds are huge investors in the stock market and in a society where a large and growing cohort of the population are dependent on private pensions for their livelihood, it feels a bit like finance capital is more a response to changing age demographics.

What is your take? I know this question is ideologically loaded, but genuinely interested in hearing takes from all perspectives.