Chances are, even if you deliberately and strategically pick to work on an OSS project that you are positively sure an LLM can’t just spit out on command, it will be capable of doing so by the time you are close to completion. In that sense, one has to either be not inclined to question “what’s the point” or have a bit of gambling mentality in order to work on anything substantial.
That’s not automatically a problem, however. The problem is that even if you do come up with a really cool idea that LLM is not capable of autocompleting, and you release it under a copyleft license (to ensure the project survives and volunteer contributor’s work is not adopted and extinguished by some commercial interest), it will get incorporated into its dataset regardless of the licensing, and thereafter the LLM will be capable of spitting it out and its large corporate operator will be able to monetise your code (allowing anyone with money wishing to build a commercial product based on it).