There's a lot of reasons Friedrich Merz has staffers that sue people who post mean things about him online. The absolute utter ghoulishness we see on display here is probably the main one, but that he is so corrupt he would have been put up against the wall 10 times over in the PRC is a close second and we should not forget that he's the exact same kind of opportunist proto-fascist as his grandfather who immediately joined the Hitlerists in 1933. Worst chancelor Germany has had since 1945.
He's not SPD tho, as for most of Merkel's reign the SPD is more like ... a kind of footstool the CDU government is propped up upon. They just really like to be used that way.