Then people should be asked before the fact: “if you upload code to our website, we can use it to train ML models and use them for commercial purposes, are you ok with that?” If people get opted into this kind of thing silently by default, that’s nasty and might even be sue-worthy.
I think opt-out should only be possible on first publish, same as e.g. GPL-v3 works, once you publish, you cannot re-claim your rights back
Then people should be asked before the fact: “if you upload code to our website, we can use it to train ML models and use them for commercial purposes, are you ok with that?” If people get opted into this kind of thing silently by default, that’s nasty and might even be sue-worthy.