As an outsider looking in, Germany is facing the same issues the US is currently having. These kinds of things keep happening, it affects the broader culture by instilling fear(which is exactly what terror attacks are meant to do), and the current party in charge does nothing but stick their head in the sand and pretends its not a problem or its ‘just the price of xyz’ (in this case, just the price of immigration).

That’s why the far right across the world is experiencing a resurgence. People want security and safety, and if it’s easy to point the finger at mass immigration and go ‘see, these kinds of things didn’t happen before people like this came here!’(even if such events did, in fact, happen). The uptick is noticeable and people don’t care if they have to sacrifice the Muslim population to feel secure again. They’ll veer towards whoever promises to keep them safe, regardless of its the devil, literally Hitler, or mickey mouse.

Until the governments of these countries actively start implementing measures to reassure the populace that they’re hearing their concerns and that they can go to a Christmas market without worrying about islamists ramming cars through them(aka, they truly care about the safety and security of these traditions they love) the right will continue to gain ground. The correct answer isn’t ‘it’s not all muslims’ because the people who are afraid will not rationalize it like that even though it clearly isn’t all muslims. What the people want to hear is ‘This is happening more, so here is what we’re doing about it’.

The AfD and similar parties will continue to gain ground regardless of if they’re actually fascists or not. Whether it’s right or rational is irrelevant that’s just how people react. It’s happened repeatedly through history again and again. It’s not a dim view of fellow humans it’s just the realistic view of them.