It's a poorly written article that confuses with its wrong translation of "Staatsraison" and omits the classification of Samidoun as a wing of PFLP, declared a terrorist organization by both the EU and the US. Supporting terrorist organizations is illegal. People getting canceled does not necessarily mean they did something illegal, and there hasn't been a discussion about criminalizing criticism of Israel.
Criticizing Netanyahu's actions is very popular in Germany. It's just true that the German government does not do that enough.