I had the same issue when I first put up my gitea instance. The bots found the domain through cert registration in minutes, before there were any backlinks. GPTbot, ClaudeBot, PerplexityBot, and others.

I added a robots.txt with explicit UAs for known scrapers (they seem to ignore wildcards), and after a few days the traffic died down completely and I've had no problem since.

Git frontends are basically a tarpit so are uniquely vulnerable to this, but I wonder if these folks actually tried a good robots.txt? I know it's wrong that they ignore wildcards, but it does seem to solve the issue