That was good. Thank you.
Ever go swimming in a pond? It's not like a swimming pool. In a swimming pool, the water is clear, the bottom is sound, humans are the only creatures there, and you can be somewhat assured of your safety. In a pond, you can't see very far in the water, the bottom is mucky and soft, there are all sorts of other creatures, and something bad may very well happen to you.
A swimming pool is not a natural system. It takes lots of work and diligence to keep it running, and even then, bad things happen. Fortunately, a swimming pool is a system with a mostly finite set of parameters to change and a similarly-small set of outcomes to manage.
Technology, startups, and BigCorps are natural systems. They're like the pond; they evolved over time without any one person managing any of it.
It took me a long time to realize that many things in life were like that pond when I was thinking most of the world was like a swimming pool. There's nothing wrong with diving into various ecosystems that have emerged out of human complexity. In fact, you can find pleasures there you can find nowhere else. But there are significant differences that nobody tells you about. These systems are emergent, they have tons of variables you might never encounter or understand, and they change based on the actions of thousands, perhaps millions of people, all of whom are not aware that they are, in effect, managing the system. (Even if they knew, no one person has the mental ability to manage all of that.)
I said all of that to say this: natural systems do not have your best interests in mind. You form a startup? Ok, there's a preexisting set of "ramps" you are supposed to get on: bootstrap, niche, unicorn, etc. People who see you in the startup world see you as being on one of those ramps. That is how they process your existence. Same goes for BigCorps: the rule there is to get along, not make waves, and have people think of you as energetic, competent, and friendly.
These are not necessarily bad systems, but you have to keep in mind everyday you interact with them that it is ultimately you who are responsible for your emotional and personal safety, not the system (No matter what they might say to you)
So yes, be disillusioned. It sounds like you've earned it. Then reflect, learn, heal, and engage differently. You've been through a tough experience. I wish you the best. If you're half as smart as you sound, you've got this.