He had to liquidate his stocks

Sure. But that doesn't mean you can't compare musk to Rockefeller or use him as a benchmark.

Using someone as a known benchmark doesn't mean they were good or bad, just that they're an established quantity. Rockefeller was wealthy beyond normal levels of wealth. It makes sense to use him as a comparison.

Totally agree. But that's the corporate sponsored capitalism that the US has voted for.

Karl Marx predicted that free-market competition would inevitably result in monopolies and the concentration of massive productive forces under a single capitalist.