Lived in Vienna for 8 years, now in Berlin for the past 3. Vienna the city is great but I'd definitely say the biggest downside are the Viennese (I know this is ironically the most Viennese thing I could say).

Basically everywhere in the German speaking world it's considered kinda weird to talk to strangers and people are quite...Shy, I guess? It's always the thing I appreciate most on visits to Canada, the US or the UK, just how talkative and nice people are.

This applies more to Austrians than to (north) Germans, and the Viennese are additionaly also grumpy and complain about everything, despite living in one of the cities with fewest things to complain about.

Also personally felt a lot less accepting of foreigners than Berlin. I far more often felt like a curious attraction and "obviously" you're not really Austrian if you're not ethnically Austrian, even if you speak German and have lived in Vienna your whole life.