The inventor of knives? The knife‘s manufacturer? The store who sold me the knife? I would say the responsibility lays 100% with myself.
I do not think it makes sense to pursue inventors for what happens to their creations, unless they actively encourage misuse.
Do guns kill people or do people kill people? Could be a relevant analogy.
https://www.npr.org/2022/06/03/1102755195/uvalde-special-ed-...
Sorry can't resist
Should McDonald's be banned? I do not think so. Anything can be misused.
To answer your question about what "good" uses there are for deep fakes: Cheaper and better special effects, available to a MUCH broader audience than before. I cannot even imagine all of the great use cases creative people will find for this.
Yes. I believe it should.
Regarding the deep fakes being good, I meant societal good. Not just fun tacky things that some people have a good time with. What social value does it bring to the world? We can do everything we need to without deep fakes. It has no value to the world.