I agree with this. Every offer I've gotten from an early-stage startup was market salary and <1% equity, often when I was engineering hire 1-5. I had conversations with founders and told them that if they couldn't meet my market rate, they had to give me 3-5% of the company. They all said no, so I did to. Then I'd get my market rate from a bank or a security company or went back to contracting for multiple clients.
Unless the company is going to be the next Google, those kind of deals don't make sense at all. But thats' generally lottery so you can keep that aside.
The other part is I have seen people fall for titles. 'Senior VP of X', while in reality you neither good exposure into org management, and let your tech skills go down the drain at the same time.
Often because of these things people lose their prime years. In most cases working for a big company, and then having a good savings and investment driven lifestyle will put you ahead of most of this kind of work opportunities.
Were you coerced into this agreement?