That's because those AI's were trained on existing "CSS tricks."
If people stop writing new CSS tricks, they will never make it into any dataset, and it won't matter if the AI can search the internet or not, because they won't be posted on the internet either.
If people stop writing new CSS tricks, they will never make it into any dataset, and it won't matter if the AI can search the internet or not, because they won't be posted on the internet either.
Essentially, mass scraping has a chilling effect.