I'm currently facing a bot attack of claudebot, who seems to be the worst of the AI crawler/scraper bots so far. It brings down the forums, resulting in errors 429, which means "Too many requests" in HTTP lingo.
The robots.txt was accessed tens of thousands of times, but successfully ignored.
There was one peak yesterday morning where I've blocked 250+ IPs. A new swarm came back today with new servers and now I'm blocking IPs in the hundreds.