> People: I don't want my stuff to be used to train models.
> Companies: To use our service you grant us perpetual license to use your stuff in whatever way we want, and also the right to sublicense so we can sell your stuff to others while granting them the same rights.
> People: Sure, here you go! Here's my art/code/voice/face/photos/videos/telemetry!
> Companies: [use data according to the license that was granted to them]
> People: pikachu_face.jpg
So enforcing what the manifesto wants to enforce wouldn't change much, if anything at all.
Disclaimer: I have pirated others' stuff (e.g. anime, manga, novels, music, I have shared memes with others (that's distribution), etc), so I can't complain when others pirate my stuff without being a hypocrite. The most I can do myself is call them out for profiting off it.