I've worked at seed, series A, and series B startups, and I think... it just depends. Only one time (a series A) did I feel exploited. That wasn't because I was an early employee at a startup; it was because the founders were sketchy and lied to us about what was going on with the company's fundamentals.

I frankly don't mind the idea that a founder is going to see orders of magnitudes more cash from a successful exit than I will, though I do think it would be great if that gap were closed a bunch.

Ultimately I worked at startups because I thought the work would be interesting, challenging, and educational (it was), because I wanted autonomy, influence, and impact (I got those), and because didn't want to deal with bureaucracy and many layers of management (I mostly didn't have to). In contrast, working at a FAANG sounds not particularly enjoyable to me. But I've never done that, so maybe it would be more ok than I think. Then again, I did join a 50-person startup and stay until it became a 10,000-person public company, and was pretty unhappy there for the last few years of my tenure, so I think it's pretty reasonable to expect I wouldn't be happy at a FAANG.

I say this to point out that not everyone is looking for the same things out of their employment experience, and that's totally fine.