It is common practice to tag such ways as permissive since it's what's actually happening on the ground. I would be very surprised if any cyclist would dismount and walk here, and even more so if police or anybody else would try to enforce that, wouldn't you? There has been some recent discussion on the ML if you are interested in more views on this topic: https://lists.openstreetmap.org/pipermail/tagging/2020-May/052880.html

Anyway, till Kössen fixes the legal problem (which I have reported to them) I have added bicycle=dismount which is the pedantically legal ground truth and should be fine with you I presume. This should at least fix most routers  (which is how I found the problem in the first place). Feel free to close this note. I'll resolve it once I hear back from the municipality.