I don't know why this is a surprise to anyone wrt Hetzner. Users have repeatedly warned that Hetzner terminates accounts of clients that they do not like. Hetzner does this without warning, even having the audacity to send you a bill thereafter.

As an example, you run any crypto related operation, even if it's a mere 5% of your workload, you will have this happen to you. You don't even have to be hosting anything at all.