We have the same (maybe even worse!) risk profile: we are being paid below market rates (because small startup), we probably don't have healthcare or benefits (because small startup), we have the majority of the burden in terms of actual leadership (because we probably have been hired with the explicit intent of having us grow the team, tech, or sales). We don't get the glory or good press that the founders do (because we're just employees, lol). We don't get the same access or transparency to the business decisions (because we're not founders).
If the business folds for the founders, they shut it down, walk away, and maybe have to file some bankruptcy. In exchange, they get to join The Magical Founders Club, wherein they can parlay their experience into speaking engagements, recruiting for new gigs, senior-level business and tech positions (regardless of skill), and funding from investors.
When the startup folds for early employees (or exits in such a way only the founders are taken care of), the result is whatever personal harm comes of stress and health issues (if not taken care of b/c of bad benefits), the net loss of however much time spent working at below market prices, potentially no portfolio work (because a lot of companies are shitty about NDAs and proprietary software), and so on.
For third or forth wave employees, sure, it's just another round of job hunting. For the first folks who actually had to build the business, well, it can really suck.
EDIT:
A minor elaboration...Micheal O'Church in an essay made an interesting claim that the founders and employees are no longer considered in the same class, compared with the 90s.
My observation has been that founders will merrily maintain three orders of magnitude of equity while doing very little more than their first few hires. In fact, they may be doing less work, because they are inexperienced and spend time doing the wrong things because they don't know any better and are senior enough they feel they can ignore advice.