It is good to make a proper distinction, in the ChatGPT context, between crawlers and agents. The crawlers go for the content to build a new model, the agents serve content to users. The last one can be very useful.

They use different user-agent strings. The crawlers obfuscate themselves and use residential proxies. The agents call themselves ChatGPT-User. Of course Cloudflare wants OpenAI to pay them for not blocking ChatGPT-User by default.