Wrestling in America has historically been more popular in rural / suburban places that have an appreciation for hard labor - whether agricultural or industrial. Those communities have tended to be less racially diverse on average than urban communities which may lend to the stereotyping that wrestling is defined by being a racist community. I would argue against that being the case, while also acknowledging, there may be a higher likelihood of minorities facing cultural challenges because of the natural demographics of the sport.
This is why when the black wrestlers took a photo together a couple years back, I found it was in recognition of their success in the face of a shared experience and I thought that was really cool and worth taking the time to celebrate. I don't think it's racist in a negative sense for them to take such a picture. If white people did the same, it would be racist in a negative sense to me. It would be celebrating success from the position of shared privilege instead of shared challenge. If this was a basketball team, it gets more complicated, because white players are not typically as successful in the sport than their black counterparts.
I think it is also worth pointing out that from a long-term perspective, there was more of wrestling country in the union than the confederacy (and a significant portion). Not that it matters specifically today, but often times, there are lots of invisible walls that take hundreds of years to tear down. Our current media structure which has the urban and rural sides pretty firmly aligned with the two major political parties, there is another dynamic in play, where we fall victim to viewing the other team as the enemy, and using visual cues like race, fashion choices, etc. in order to make those determinations. So that acts as an amplifier to an already sensitive situation.
In summary, I think wrestling is not a racist sport, but there is a decent amount of nuance to consider how each race may experience the sport in its current form.