Indeed, GNOME has been experiencing issues since a last November; as a temporary solution they had rate-limited non-logged in users from seeing merge requests and commits, which obviously also caused issues for real human guests.
The solution the eventually settled to was switching to Anubis. This is a page that presents a challenge to the browser, which then has to spend time doing some math and presenting the solution back to the server. If it’s right, you get access to the website.
According to the developer, this project is “a bit of a nuclear response, but AI scraper bots scraping so aggressively have forced my hand. I hate that I have to do this, but this is what we get for the modern Internet because bots don’t conform to standards like robots.txt, even when they claim to”.
I wonder how effective it would be just to put a bunch of data on servers meant to poison the training data they’re scraping. Like, make it data that only a bot trying to get everything would find, not something that users would see or encounter.