So let's say full dive is being worked on, but before all the health hazards and certifications are met, it's at least 5 years of closed beta-testing.
Because it's quite a milestone, there's a lot of money in it and interest. You're invited to the beta-testing. Quick calculations show that if you treat it like your day job, submit your mental states during play you can probably retire from work after those 5 years, and live with your life standards before the beta testing.
It quickly turns out you can multiply the ammount of money you make, however, if you put yourself in high-stress, painful situations. It's clear they want a guinea pig to see the limits of human mental health, to see what happens if your brain is convinced it dies and does degenerate, morally wrong shit day in day out.
You can earn even more by streaming to public, and you don't have to do boring shit like editing, it's all impropmtu reality show and even if you're not doing anything special, there's tonnes of viewers because of the nature of the tech and the stream.
Would you participate in beta-testing? Would you cross the line? No matter what happens, you'd go in history as pioneer of the tech.