Right, you definitely have to understand what you're getting into. Being a successful startup engineer is probably a specialty in itself, that requires a mix of business knowledge and software knowledge.

Many startups are beginning to offer the ability to convert your ISOs (which the SEC requires you to exercise within 90 days regardless of company preference) into RSUs (which allows the company to set the terms, I believe Stripe and some other big ones offer 7 years). You do lose some tax benefits of ISO treatment when you convert to RSUs, but this is just something you need to understand going into the deal and consider part of the offer.

Another thing being offered frequently is early exercise. If you join a company early enough you can often afford to exercise all your options outright. If you couple that with an 83B filing you can eliminate your tax liability until you sell your shares. Frankly I probably would not consider joining a company without early exercise at this point because of the exact issues you pointed out.

It's not as straight forward as cash, but you can definitely create a mental model for thinking about the risk.