Just that it’s inappropriate. Someone saw your pet and reported it because it was offensive to them. It may have been multiple someones, we have no way of knowing, but it only takes a single report. Blizzard does not have a hard and fast list of what should be common sense to avoid using because things are ever fluid and changing, and we as players are creative when it comes to trying to sidle around the rules.
This isn’t anything new. I’ve found posts from nearly three years ago with someone proactively trying to get the terminology banned from being used as a name because of the havoc it’s wrecked against the human population.
There is also a history from as far back as 2020 that people were getting sanctioned for using variants (as previously mentioned, the player base can indeed get creative). You might think it amusing, but someone who lost several close friends or family members due to it aren’t going to be gaining a chuckle from your creativity.