Granted I was only in Berlin for two weeks, but all but two people I interacted with didn't immediately switch to English if they had something to say beyond the transaction. (A bus driver and a currywurst seller, who seemed genuinely annoyed that I was a tourist)

My experience is this: In Austria they want to speak English. In Germany they want to speak German. On a Lufthansa flight it's 50/50 whether they ask me questions in English or German.

This happens that people approach and start speaking in German, but I never had a problem that they didn't want to speak English once they realized I dont speak german

It probably depends on where in Germany you are. One time in Berlin I started on my broken German and they reacted with a big question mark, and then back to English.

And 20-30 years ago you had to use German most places.

Germany has a very big immigrant population, so plenty of people who don't look German at all but speak fluently or even natively.

About English, they are very self-concious and they often say that they speak "a little bit" when they are for all intents and purposes fluent.

We used to joke that most Germans don't speak English until you get them drunk, and then they are more fluent than native speakers.