To solve all this, it's pretty simple, and the U.S. actually used to do it: heavily tax the super rich. Heavy taxation and then appropriate use of those funds for education, R&D funding, infrastructure, etc. is actual trickle-down economics. And mega corporations should be heavily taxed instead of holding the country economically hostage. They jumpstart their companies off of government funding and R&D and then act a…
There are three places that capital can come from:
* the state, but we have voted year in and year out for tax cuts and spending rises, so the state is bankrupt. Not only is it not a source of capital, it is a major customer for it
* normal individuals saving and those small amounts being aggregated by banks etc. But rampant (and government supported) consumerism means most people are also consumers of capital not sources of it. Incidentally an example of the opposite of this is Germany where ordinary people save a lot more and don't have OTT mortgages and credit card debt. Mysteriously they have very few billionares...
* Billionaires. Which given the US (and UK where I live need their capital AND cannot get it elsewhere are able to charge a premium for it and cannot really be taxed etc without pain spreading all over the rest of the economy.
But if you try and tell people to spend less, save more, pay their taxes and accept less services in order to have a better, fairer, more equal, ultimately richer life they bulk...