Oh this has been well studied. There’s a whole swath of papers teasing out the confounding variables, and wealth is not the only one. These papers estimate the correction factor one would need to assign a portion of causation to the degree, and a portion of causation to the inherited wealth, and basically nobody is claiming that wealth is the complete reason, and nearly all papers assign a healthy portion to the degree after controlling for wealth, for two reasons: one, because unsurprisingly 5 years spent studying actually results in learning a few things and gaining some skills that are useful to industry, and two, because industry relies on credentials, and people without PhDs cannot get research jobs, regardless of how good they are.
There’s no doubt in my mind that things are biased for the wealthy, none whatsoever. But consider patents - they have no degree requirement, and the number of patents granted to people with a bachelor’s degree or less is in the low single digit percent, it’s a landslide for people with formal research experience.
> The reality is that for a lot of people getting advanced degrees leads to nothing
What does “a lot” mean? Do you have a source for this claim that passes statistics 101?