It is based on science. ‘The German government's vaccines agency, the Paul Ehrlich Institute, said since Thursday it had noticed a "striking accumulation" of cases of a rare kind of blood clot on the brain, cerebral venous sinus thrombosis (CVST) in people who'd just had the vaccine’.
Now, the figures are small, but Germany is ‘risk adverse’ hence the suspension. You can argue that the case for continuing outweighs the risk of not vaccinating, but that is not the model Germany operates under.
So, yes, it is that simple, but it ain’t politics.