Most startups are open to trading cash for equity if you ask. Many even offer it explicitly. Investors also encourage it, e.g. see Index's Rewarding Talent guide: https://www.indexventures.com/rewarding-talent/balancing-cas....

When I make someone an offer, I give them a spreadsheet where they can plug in different salaries and equity stakes to see outcomes based on future funding events, valuations, and exit scenarios. Without exception the people who've leaned into equity have turned out to be the best performers and ended up with higher salaries anyway, but a majority favor cash up front.

Be the change you want to see in the world?

As you find reasons to object to that, many of those reasons are likely the same shared by others and make this a vastly less common arrangement, because someone has to take on the massive initial risk to start and fund the business through the unavoidable period of initial losses and probably wants to see a way to having a compensating upside in the event of success.