I can't answer for everybody, but my (German) university is prohibited from doing so by law. We are state employees and as such our university needs a comtract

I can't answer for everybody, but my (German) university is prohibited from doing so by law. We are state employees and as such our university needs a comtract with the people runnimg services that process our (or our students) data. Obviously our university isn't gonna make a 10k€/month contract just because some prof wants their mail forwarded to gmail. Especially not if they are not working here anymore.