no because it's hardly doable now, and not doable in the long run.

First, after many memory optimisation, I am still using 4GB for my Redis-based graph.

Can you do it on the phone? Yeah, but not when nostr will be 10x what's now.

Second, you don't gain anything computing the rank yourself if you trust the provider with computing the graph. You might as well use the provider's ranks directly. Computing the graph requires downloading 10+ GB JSON and doing ~400k signature checks.

Third, counting follow list alone, the graph needs to be updated 18k times every day, to be always up to date, which is expensive and changes the ranks.

These are he number for the "whole" graph. A number of people might think that you don't need the whole graph, you just need 2-hops (follows of follows), but I argue that the experience is going to suffer dramatically. In every social media under the sun you can search, at least by user name and find the person. Imagine saying that in Nostr you can't because your locally computed social graph (which is graining your battery) isn't big enough. Like wtf.