Could you visit that forum thread please @ti-lo and make your case there? I'm looking at taginfo, it says there are tens of thousands of such keys, which seems quite significant to me. Neither are all uses of OSM data purely mechanical (i.e. open OsmAnd and click on details on shops having service:vehicle: tags).  Nor are all vehicles cars (e.g. see "Marine" in this shop name).  Also see https://wiki.openstreetmap.org/wiki/Key:service:vehicle: - just because tags become popular through ATYL policy does not mean people can go and start removing them without discussion. And fact that discussion didn't happen half a decade ago does not mean the consensus was made to do X - quite the contrary. But all that should be better discussed at wider community forum then thru this rudimentary changeset discussion interface (which also happen to have much more limited audience).