I'm quitting my PhD

This doesn’t seem like an entirely fair take. Nobody has perfect expectations fresh out of undergrad. PIs chasing funding is real, and using those funds on grad students who are excited but don’t know what they’re getting into is extremely common. The one thing that is less common is providing zero resources & guidance to get the job done. This definitely sounds like at least as much advisory failure as student expectation.

It's always about grant money. Especially with anything that starts with Quantum

Everyone needs to understand something important: a PhD is first and foremost an apprenticeship. It is your opportunity to study under someone who has done a specific kind of research, and learn from that person. If that relationship isn't a good fit, the PhD itself won't be a good fit: it's like trying to learn neurosurgery from a cardiac surgeon. You cannot fix this with reading or online lectures, the apprenticeship is the whole point.

Occasionally I run into students who have these advisor mismatches and my instinct is to try to help them. However what I've learned is that good intentions (try to advise a student who is interested in a different area) don't actually translate to good outcomes. I am monomaniacal (only) about the research that interests me, and that doesn't translate into other areas I'm less familiar with. They will be frustrated with my lack of expertise in those other areas, and I will end up frustrated by my inability to properly advise them. In the worst case, that bad fit can turn to resentment against the entire scientific process (I see this process starting in the post above.)

If the author of the post wants to pursue a PhD, I would first urge them to stop for a while and not think about research: just do something else. When and if they've reached the point where they are bored to tears with whatever they're doing (I recommend taking a "real" job for a while) -- and can only think about the research they're missing out on -- then go figure out whose papers are actually exciting to them. Then go find out how to work with that person, whatever it takes. Sometimes there are ways to work with someone that don't require a formal PhD admission, and enough persistence can make the difference. I'm not saying this is easy. The point is: don't do it because it's easy, do it because you want to do it enough that it doesn't matter if it's hard.