Hi,
Why did you retag https://www.openstreetmap.org/way/959770729 from a riding arena (leisure=pitch + sport=equestrian) to an equestrian centre (leisure=horse_riding)? To me, this area looks like a riding arena, so the previous tagging was correct, compare
https://wiki.openstreetmap.org/wiki/How_to_map_a#Riding_centre_(equestrian) and
https://wiki.openstreetmap.org/wiki/Tag:leisure=horse_riding. A single riding arena is not an equestrian centre, just as a single soccer pitch is not a soccer stadium or sports_centre (from https://wiki.openstreetmap.org/wiki/Tag:leisure=sports_centre).

Perhaps this riding arena belongs to an equestrian centre that has not yet been mapped; in that case, you can map it as an additional object (node or area) without retagging the arena, example: https://www.openstreetmap.org/way/159628079#map=19/35.556070/139.650131&layers=P

If you want to reply that this is none of my business and that I should leave you alone because I am not in Japan, I would like to point out that such misuse of the tag leisure=horse_riding is the main reason why this tag is not yet rendered on OSM Carto, see https://github.com/gravitystorm/openstreetmap-carto/pull/3660#issuecomment-462927711

I also think that https://www.openstreetmap.org/way/1182217067 looks like a riding arena and should be tagged with leisure=pitch + sport=equestrian instead of leisure=horse_riding.