[unnouinceput]

1- It's on internet. If it's on Google site then it's free. If you want then use robots.txt (not that ever stopped google's spider to index your pages)

2 - Code was trained from GitHub. GitHub is Microsoft. OpenAI is Microsoft money. So Microsoft trained its AI on Microsoft code. You disagree? Then GTFO from GitHub and don't feed Microsoft your code anymore.

3 (the most important point) - Q: "Can this start breaking the ad-based model of the internet, where a lot of sites rely upon the ad income to run servers?"

Fuck YEAH!! please do so. I hope the shit show that ad model is crashes and burn to the ground. You can't use internet without having a solid armor on you with uBlock Origin and/or NoScript (or PiHole if you want the same readable experience on rest of your house devices).