I to have been trying to go "completely off grid". While I do nothing illegal nor have any intention to do so, I've taken the challenge to try and get Big Tech (and Big Bro) sealed out as much as possible.
Reality is that the best I have found is to pick a carrier that requires a government warrant to track my information.
Compare this to Google, Facebook, Amazon, Apple that are selling every speck of data they can on each of us both to the government, from Federal to Local, as well as advertisers. They will all provide VERY DETAILED location and DNS information on you to authorities WITHOUT A WARRANT.
While they claim "anonymous tracking", reality is an advertiser can tell where your phone spends the night, then look you up via public record, then literally map out your entire life (background checks) and behaviors. There are services that aggregate and present in easy to digest formats to anyone that wants to purchase the data.
Note that all VPN's, if handed a government warrant, will provide information on you.
So unless I'm missing something, best I can do is limit my behavioral information collection to my wireless carrier which still requires a warrant be issued in order to track me. For me that's good enough since that parking ticket in London from 20 years ago likely isn't going to draw Interpol, FBI and NSA effort to get a warrant. And keeps the Matrix from tracking me and selling me another Pixel 6. LOL
I'm new to this privacy game. Set me straight if I'm off. Always up to learn.