Re: Open Source Licenses are already sufficient.
#1 is the standard operating model of the social media companies. Simply argue (but not in so many words, obviously) that you've built something so large that you can't possibly police it, except with AI, which in the case of the GenAI companies will create a lovely closed loop where they have to be allowed to do what they want.
The lesson from the social media companies is that we need to stamp hard on that argument early, before they grow too large to stop.
We need a legal framework for GenAI (and for the stuff that everyone was previously calling 'AI') that says if it would be illegal for one of your employees to do it then it's also illegal for your algorithms to do it. Copyright infringement, discrimination, recommending smut to kids, promoting terrorist content... whatever. If your algorithm does it then you're responsible for that in the same way that you would be if an employee did it.
As additional weight behind the law, make advertisers responsible for anything they fund, so if an ad appears on illegal content, the advertiser is also responsible for having funded it. That would clean up the behaviour of big tech unbelievably quickly.