I understand why Queen B or T Swift aren't doing it, but the only moral activity (beyond survival tasks) that a "good billionaire" can be engaged in is redistributing their wealth to marginalized workers.
You can figure out your next album / tour or how to benefit your friends and family once you get to 999M USD.
There are plenty of places where they don't lie to you about PTO benefits, pay, and have some group insurance plan/program.