Then maybe funds like Blackrock, Vanguard, should be dismantled as well.

Why? "Owned by Vanguard" is the closest possible thing to "owned by the American public". What do you think Vanguard is and where do you think their money comes from?

Downvoting because parent is clearly referring to corp gov activities and it’s insulting to insinuate they don’t know what an asset manager is.

Everyone should be their own asset manager? The devolution of voting has already started, so not sure that direction has much merit.

Maybe just restrict index funds from interfering with whatever business they own? Index funds are ultimately a dumb momentum-based business model that just buys whatever companies are doing well at the moment and sells whichever aren't, but bear no risk themselves outside the economy shrinking. Not sure why they should have any say in how the companies they own operate, it seems like a complete competence mismatch (dumb ones with little risk controlling the smart ones with the skin in the game).