Germany, like all the Western necon powerhouses (US, UK, France) are dealing with their neocon chickens coming home to roost.

Power costs went up by 4-6X in Germany because the US blew up the German-Russian gas pipeline to push further NATO expansion into Ukraine and try to collapse Russia like the USSR.

Average Germans don't give a shit about who controls the Donbas any more than average Americans.

A conman demagogue like Trump in the US and the AfD in Germany are symptoms of the failure of mainstream parties to deliver value to their voters, just as you say.

The Nazis never had majority support. Hitler didn't come to power because Weimar Republic was doing well. Hitler came to power because the German oligarchs who had done so well under the Kaiser didn't like democracy and undermined the new government. The Treaty of Versaille and some other big issues played roles of course.

Fascism is on the rise in the West because the oligarchs are undermining democracy again.