> long-distance busses (like the one between Munich and Zürich)
Zurich is too deep in Switzerland to be covered anyways. (Salzburg, Kufstein, Basel Bad Bf, etc. however are in Austria/Switzerland but part of German rail rates and included in 9€ tickets)
And that DB bus doesn't exist anymore since the new electrified railway line to Lindau was opened two years ago, as Munucih-Zurich got way faster by train. (I guess Flixbus still offers it but Flix isn't part of 9€ either)