Startups, from an employee standpoint, are not about getting rich off of the company succeeding. That won't happen. They're about building your skills in a fun environment, socking away as much cash as possible along the way, and leveling up your value by burning through a bunch of fun, hopeless companies in a short period of time.
The fact that it took this one 4 years to cycle itself is actually the only downside I can see here. Everything else is what you signed up for (whether you realized you were signing up for it or not).
Now go out and double your salary.
Career paths are not a common thing in startups as the structures are mostly flat and in general you get rewarded for just doing, and rarely are you on a career path or career development plan. So my answer is this. If you have a passion to be a founder and have an idea or two, start now, be a founder, look for a co-founder with your passion but complementary skills. If you are unsure or aren't interested in the startup path in terms of being a founder, find either another startup to join or start applying for more traditional enterprise technology (assuming you are in dev) roles.
Don't believe the tech echo chamber that makes everyone believe there are only successful startups out there. There is a reason we use the word "unicorn" for very successful ones.
I'm confused by the question. What other choices did you expect?