Google doesn't put GCP compute inside Equinx Slough. I could perhaps believe if they have a cage of routers and perhaps even CDN boxes/Edge, but no general cloud compute.
Google and AWS will put routers inside Equinx Slough sure, but that's literally written on the tin, and the only way a carrier hotel could work.
Then why do they obfuscate the location of their servers? If they were all in Google datacenters, why not let me see where my VM is?
Security reasons, I presume? Otherwise it would be trivial for an adversary to map out their resources by sampling VM rentals over a moderate time-period.
I’m very naive on the subject here - what advantage would this give someone?
The knowledge of blast radii.
Gives whole new meaning to “reverse engineering”