Hi,
https://www.openstreetmap.org/way/1240892116 and https://www.openstreetmap.org/way/1240892117 look like riding arenas and not like riding centres (leisure=horse_riding). Also it does not make sense to map one arena inside of another. In OSM riding arenas are usually tagged leisure=pitch +  sport=equestrian and iD has a preset for them that does that.
Compare
https://wiki.openstreetmap.org/wiki/Tag:leisure%3Dhorse_riding
https://www.openstreetmap.org/way/204551023 (correct example)