"Lil Nas X’s ‘Old Town Road’ Was a Country Hit. Then Country Changed Its Mind"

Rolling Stone:

it debuted on Billboard’s cross-genre Hot 100 chart, the Hot Country Songs chart and the Hot R&B/Hip-Hop Songs chart all at once.

Lil Nas X’s career on the country chart, though, was short-lived. Billboard quietly removed “Old Town Road” from Hot Country Songs

...

"While ‘Old Town Road’ incorporates references to country and cowboy imagery, it does not embrace enough elements of today’s country music to chart in its current version.”