On the graphene website, I would recommend reading their full “Features” page. It explains a lot.

In addition also look at /e/os/ as well. I am currently de googling from my primary phone to a secondary phone (on my old phone; I flashed /e/os/ on it. And it have no Google apps. They have micro g integration built in. And I use “shelter” to create a work profile to isolate the apps that are not privacy focussed and they forever live in that sandbox, and you can turn off and on those apps with one click".) Changing my email address to govt/doctors/etc. And backing up data from google account is taking the longest before I disable that completely.

How do you ask any company to delete your data? Give them your id document?

Perhaps Qubes.

By if you have ESIM, the wipe deletes the Sim as well…

Clippy designer.

I kinda took out my old phone (Sony) and flashed on that… And running parallel while I degoogle myself… Takes some time to change all email registrations from govt. And tax authorities to other external services like docs, banks and stuff…so doing dual phone for a fee weeks and then dropped main phone (fairphone5) to fully shift on e/os phone (sony)… And then will reset the ex-main phone (ff5) when degoogle is complete… I am too busy these days so it’s taking very long. (Also clean up Google inboxes and then back up vs. Backup and then clean up old inboxes is a struggle for me). Once fully complete I will flash ex-mainphone FF5 with e/os as well and switch to it And then use the 2nd phone to shift my partner and kids slowly. And in a year or next upgrades I think I might buy my family older pixel phones and flash e/os on them.

Maybe you should also get a side phone to start the project.

What phone do you want to flash on? Is it in this list? https://doc.e.foundation/devices