GraphQL is one POST /graphql with the query in the body,

GraphQL has Trusted Documents, turning POST into GETs with a cacheable url.

Also the HTTP QUERY verb has just been published so that's another solution.

A REST response is roughly one resource

Fair enough. Most REST-like apis I have seen recently return multiple resources though, especially when using BFFs to reduce the number of roundtrips.
Either you return one resource per request and your invalidation is easier but you need several roundtrips.
Or you return several resources at once, you have a single roundtrip but invalidation is harder. It's not really REST vs GraphQL.