Bug bounties are cash rewards for finding bugs. Has anyone done a crowdsourced bounty for adding a feature to linux? E.g., driver support for a certain peripheral. If enough people want it, and drop $10 each, seems like it would quickly become worth it for someone to code a fix.
Many.
Projects don’t usually do bounties, but individual contributors do.
Most things can be implemented, but getting it merged and maintained mainline is harder.