>>53878067Just because something can be checked and/or countered doesn't mean it's a healthy presence within the metagame.
There have been plenty of Pokemon that have been banned that have plenty of checks and counters. During the Zama-C suspect in Gen 8, Zama had plenty of checks and counters within OU and it still got banned because it's mere presence in the tier warped the entire meta around it and the players deemed it not fun. Bronzong completely fucks Lando-I eight ways to Sunday and it has been consistently banned the moment it got access to Sheer Force. AssaultVest Skuntank handles Gen 6 Greninja. Tyranitar handles every Nagandel set.
Hell, Zama-C gets completely walled by Dondozo 100% of the time and I still think allowing it in Gen 9 OU is a mistake.
The players don't find Espathra fun to play or against, and thus, it's banned and stays banned.