While limiting AI can make sense and it's particularly important to keep contributors responsible (for example, not allowing pull requests submitted directly by AI), it's outright dangerous to ban the use of AI altogether. Not using AI for vetting code and bug hunting is going to make your software very vulnerable. AI can find bugs in your open source repo that no human might find and you can bet your ass that attackers will use AI to find exploits.

It's only a matter of time until code only written by humans is widely going to be considered unsafe.