As nobody seems to have thought of this up to now: one way of working around the issue would be to find out who, outside of JOSM users using JOSM, is using the key and causing so high usage and asking them to stop.
As nobody seems to have thought of this up to now: one way of working around the issue would be to find out who, outside of JOSM users using JOSM, is using the key and causing so high usage and asking them to stop.