Tbh, I hear that almost exclusively from native Germans, though that might be because I had an Irish sounding maiden name and people figured I’d be insulted by potato jokes. Weirdly, I don’t hear much teasing of Germans from immigrants. I do it, like the other day I left work in socks and crocs and pointed it out as a final step of my Eindeutschung to my coworkers, so not really cutting, but I still don’t hear even light teasing much from others. The most I see is loaded eye contact whenever something is really German. Things like unbelievable bureaucracy, or very precise engineering, or an absolutely terrifying thing that’s for some reason aimed at children.