Yes, these platforms will be used to immensely harmful effect--the only limit to the damage they'll do is the human imagination. But I'm not sure how this brings the entire experiment to an end, unless it brings humanity itself to an end.
Once humans figure out how to do certain things, they're permanent parts of the human experience because the knowledge can't be unlearned. (Think about building nuclear weapons, for example.)
Humans know about social media now, so even if certain platforms are done in by deepfakes, we'll keep building social media platforms. Or is that what you mean? That Twitter and Facebook and the like will be done in, but new deepfake-proof platforms will replace them?
