This isn't specific to microservices. I've seen two organizations with a lot of content have their website brought to its knees because multiple AI crawlers were hitting it.
One of them was pretending to be a very specific version of Microsoft Edge, coming from an Alibaba datacenter. Suuuuuuuuuuuuuuuuuure. Blocked its IP range and about ten minutes later a different subnet was hammering away again. I ended up just blocking based off the first two octets; the client didn't care, none of their visitors are from China.
All of this was sailing right through Cloudflare.