The expected public_transport tag for highway=bus_stop node is public_transport=platform.  Please see https://wiki.openstreetmap.org/wiki/Tag:public%20transport=platform?uselang=en-GB
and https://wiki.openstreetmap.org/wiki/Tag:public%20transport=stop%20area?uselang=en-GB
the latter of which is for use on a stop area relation.  There is no public_transport=stop.  Repeatedly guessing at tags (eg to try to make iD warnings go away) is not going to help improve the map.  I've set public_transport=platform.