It's due to their users and associated behavior that tor Exit nodes have an elevated bad reputation.
> https://developers.cloudflare.com/support/firewall/learn-mor...
> Due to the behavior of some individuals using the Tor network (spammers, distributors of malware, attackers, etc.), the IP addresses of Tor exit nodes may earn a bad reputation, elevating their Cloudflare threat score.
Customers of cloudflare have an option to improve experience for Tor users
> Beyond applying firewall filters to Tor traffic, Cloudflare users can improve the Tor user experience by enabling Onion Routing. Onion Routing allows Cloudflare to serve your website’s content directly through the Tor network, without requiring exit nodes.
Email the sites where you have issues and ask them to enable Tor routing.