This is a social problem enabled by technology, so the solution is necessarily a social one with technology to support it.
I don't know if this fits existing legal frameworks or if we'll have to put new laws on the books, but we should treat this as harassment. We should make it clear to younger generations that this isn't okay and why.
On the flip side, I imagine people will get more defensive about their biometric data. We'll probably start to regard photos and voice recordings as being very private. It probably won't be as socially acceptable to post them. It will probably be more normalized to use an avatar and synthesized voice on things like Zoom calls.
But this is all very speculative, so I won't be too surprised if things go very differently than I anticipate.
Which creates a subsequent issue of it being completely impossible to authenticate the person you're talking to. Which will inevitably lead to companies being completely cored out by exploiters who, on a long term, infiltrate networks and give instructions to subordinates 'as the boss' which lead to companies failing.
The bad keeps happening because there is no financial incentive to change. Platforms are all too happy to look the other way because there's no risk to them. Change that.
As much as I find them distasteful, I'll agree that deepfakes should be outlawed as harassment the same day someone holds teenaged girls spreading rumors to the same standard.