Even if we completely toss out IP, isn't an artist free to release whatever version of their content they want? I find that AI poisoning seems to be a speed bump at best, but I don't see an issue with artists using it if they wish. If anything, it gives a fun challenge for machine learning developers to try.

Of course. Just like a company is allowed to release software which whatever copyright measures in place.

I also never said that artists should not be allowed to do this, just that I hoped their methods were defeated. The same way I hope copyright protections are defeated.