Alright, alright, hold your horses.
I actually consider to have done my homework prior to switching over.
#GrapheneOS servers monitoring? Sure, but every other OS will need a server-backend for monitoring of basic services, it's up to the user to either outright switch servers or detach specific services (such as using ntfy for push, MLS for location services, etc) wherever possible. Without such a backend, smartphones won't really function.
Fingerprinting users? You can say that, but that would go directly against their own incentives.
I can use TOR just fine for literally everything, updates included.
From my packet-sniffing testing I found no issues with phone-home data. No immediate red-flags.
You do realise Tavi recommends Graphene, right?
And the reasoning is simple - DivestOS and GrapheneOS solve very different problems. DivestOS is catered towards older devices and general compatibility to keep them as secure as AOSP allows for as long as possible. GrapheneOS caters for newer devices and takes advantage of newer hardware to enhance and actually enforce device-hardening.
They're not even competing in the same space.