This makes no sense: "While simultaneously, big tech engages in non-productive stock buybacks to prop up valuations with cash resources better used for new R&D or M&A"

What?! It isn't like the money used in a stock buyback just disappears from the economy. That money will be turned around and invested in some other company, that might actually needs money and has a purpose to use it for. That is how the economy works.

It is much better at a macroeconomic level for a company to return cash that it doesn't feel it can efficiently use to its investors, rather than try to chase some investment that won't have a good return just because you have the money.

This whole site seems pretty lacking in terms of understanding of how things work.