Being in academia is absolutely exhausting
Unhappy people in STEM is the norm. And while people love to romanticize doing science, I would be the first to yell: "Oh god, it sucks, holy shit, keep away."
Your bosses are unhappy with your progress always. It does not matter if you're fast, or you're too slow. If you're too fast at research, then why are you so sloppy? If you're too slow at research, then why are you so unproductive? If you do your research differently, then why? If you do your research similar to your bosses, then why aren't you independent? Yes, there's all this talk of collaboration (Koombaya) but really non-faculty researchers are paper producing mills. You ask your boss to give you feedback, and sometimes they ask as if you personally offended their mother. The expectation is that you produce this perfect paper and they stamp their name on it without much thought.
My years as a postdoc is a completely humiliating experience with non-great bosses. It is amazing how we talk about how it is unprofessional to air your dirty laundry... But I have had unprofessional things done to me.
It's a publish or perish culture, but there's also other evils that permeate it. It's an absolutely toxic culture. Yes, there's an external force that is now destroying academia, but personally, I think it was hastening its illness. Academia thrives on a scarcity mind-set and it makes people vindictive and cruel. There are academic leaders, there are only managers.
Heed my warning- only go into academia, if you can stomach it.