In tirreno (our product), we catch every resource request on the server side, including LLMs.txt and agents.md, to get the IP that requested it and the UA.
What I've seen from ASNs is that visits are coming from GOOGLE-CLOUD-PLATFORM (not from Google itself), and OVH. Based on UA, users are: WebPageTest, BuiltWith, and zero LLMs based on both ASN and UA.
Openclaw agents use the same browser and ASN that me and you use, also the llms.txt (as shown) is displayed as a normal blog page so it can be discover by the agents without having to fetch /llms.txt at random.