The problem is everybody is using it and its impossible to move to signal etc

impossible

Is it really? Is someone holding a gun and forcing you to use it? You can always quit if you really wanted to.

I mean yeah, but i would have no contacts to anyone, here in germany we literally use nothing else, contact to teachers for assignments is lost, couldnt text with my family, would have no contact to my friends etc

But what if you messaged them via SMS, would they refuse to reply back?