My school has provided us some emails with a custom domain (not @gmail.com but @myschool.smth) and we as students are only able to login via gmail, however i obviously do not want that. What can i do to prevent that? I tried logging into the email via Thunderbird but i get blocked because my administrator doesn’t allow that.
As others have said, at this point you don’t have a whole lot of choice; you pretty much have to use what the school provides you.
BUT, what you can do is try to rally other students to your cause. You pay the university, which means that students in numbers have influence over how the the university operates. I think your best chance to enact change is to create a petition to get the university to change to a more privacy-friendly alternative, and put together a proposal on how google and microsoft are harmful, and why your proposed alternative is better.