@danielpree @linuzifer I have been using these services and manufacturers for a long time, but only in parallel and occasionally. My main systems and services have been open source solutions for years. Apple products, for example, are more of a gimmick, a technical curiosity, or useful for monitoring my heart condition. Google, because basically everyone has an account there, even if, like me, it's only for YouTube (where I used to regularly post videos about Linux and such until two years ago). Amazon, because it's convenient to order a few everyday items there that you can't find in local stores. And I admit to watching the occasional series on Prime Video. But now it all has to go!
The only thing that will hurt is giving up a de-Googled smartphone with GrapheneOS, because of the calendar function and synchronization with my other computers when I'm on the go. I guess that means a return to the good old pocket calendar.