I had everything working as I wanted and as I expected, then something changed.
I'm assuming BTT updated itself but previously in apps I had only the app's touch bar showing when in any app. Now, suddenly I have the app touch bar and the mac os default bar, collapsed, on the right side of the touch bar.
For "All apps" I have "Touch Bar Configuration for: (All Apps)" set to "Show App Default Touch Bar ** Hide Control Strip in case BTT bar is activated".
Am I doing something wrong? Did the behavior change on purpose?