I'm sitting in my hotel/B&B room in Berlin as I type this.
Traveling in Germany is great right now, as far as I'm concerned. My stay in Berlin really does not seem that much different than previous ones other than some indoor/transportation mask use. As noted by others, there is little mask use outdoors, but masks are required in restaurants, shops, and on public transportation. Some places require N95; some just require a medical mask; just go with N95 and you don't have to worry about it.
Restaurants are open inside and out. I've eaten inside twice at off hours to avoid crowds. I wear a mask to enter the restaurant and to move about the restaurant (per local regulations). I was asked about vaccination but not required to show proof.
My B&B is the same as the last 7 or 8 times I have stayed here. The owner is vaccinated, and guests must be vaccinated. No one in the 4-bedroom B&B wears masks. Breakfast is around a communal table with other guests (an optometrist couple from Switzerland and a journalist from elsewhere in Germany). I stayed at a slightly larger Gästehaus in a small town in Bavaria. Masks were required for movement around the facility (local regulation). Breakfast was served at individual tables instead of the typical buffet. In Saxony, my hotel required masks only in the elevator and in the dining room.
Large museums are open as usual, but most require reserving (free museums) or buying a time-specific ticket online. Some small museums have reduced hours and ask for a call before coming. I had zero trouble getting tickets for the museums I wanted to see on the day of my visit.
I attended an outdoor concert. People needed a negative test (testing facility onsite ) or proof of vaccination to enter.
All my favorite places in Berlin are alive and well except SpätzleExpress, a quick-serve Swabian restaurant in Kreuzberg, which closed during the pandemic.
People seem to be fine with me being here. I think there is the assumption that visitors are good global citizens who have had their immunizations. Conversations with people have been easy and comfortable. No one seems to be afraid of me bringing them COVID.
I got my COVID-19 rapid test this morning for my return flight in 2 days. Easy-peasy. Results e-mailed to me as a pdf, which I was able to upload to Delta's partner for managing return COVID-19 testing.
I have much enjoyed my trip. COVID-19 has been a minor inconvenience at most. The train strike is a bigger inconvenience.