I tend to agree with the logic that name="Name language 1 - name language 2" model should be limited to places with two equal official languages. This is not the case in facility municipalities. This is also how things are documented on the wiki, and all of Belgium was mapped (except for the facility municipalities bordering Brussels). We are discussing whether the current policy needs an update here: https://community.openstreetmap.org/t/language-facilities-how-do-we-map-them/108026/10
Stein, it would be useful if you shared your opinion there. Closing this Note as discussion should happen there.