The therian and otherkin communities really do harbour a lot of unexamined racism.
And I understand why. For many of us, our identities are inherently based in wanting to be seen, treated, as something other than human. We're often eager to disavow humanity, having spent so long being forced into that role, and so we embrace ideas of dehumanisation. But we don't often consider that alterhumans of colour, who have long histories of being treated as subhuman and having their humanity denied, might have more complex relationships with these narratives.
As a community in the internet age, we have the myths and legends of the whole world at our fingertips. But we often give very little care to the meanings of those myths and the cultures they come from. (Are you actually a human possessed by an Algonquin spirit of starvation, after falling prey to greed and the exploitation of other people? Or are you a woods monster with a skull-deer head? Because the former is not the latter, and if you actually are the former, a lot of Native Americans are going to be rightfully upset by you, as that spirit represents immense amounts of cruelty that was done to them and is still being done to them.)
And then there are the myths and legends that are explicitly tied to racism. The New Age narrative of starseeds and ancient alien ancestors originates in white supremacy (we never see Black alien progenitors, but we do see explicitly "Nordic" ones), antisemitism (anything to do with the world being secretly run by alien lizardfolk, which have widely been understood by Jewish scholars as code for the Jews), and literal Nazi occult practices. While some starseeds disavow racism, disavowing it personally is not enough- not when the community continues to circulate white supremacist beliefs.
And then of course there's the police dog thing. No, it doesn't make you evil to have been a police dog, or to have enjoyed having been one. No one can expect you to have understood racism as a dog. But you have this body and mind now, you are aware of racism now, and you are aware of the baseless cruelty of the police, the countless Black and Brown communities that have been terrorised by the police and K9 units. You have the choice to keep condoning this system, or to learn about it and the harm it does. Perhaps that's what you're meant to do as a dog in this life- perhaps that's why you're here, why you've been given this mind and this awareness in this current time. To become a better, more compassionate being than you were in the past.
This isn't to say you're not a dog who served the police, or a kitsune, or an alien from the Pleiades, or an animal who enjoys dehumanisation. (I'm that last one myself!) But we have to understand that when we talk about these things uncritically, when we're wilfully ignorant and don't do the research or care about how these ideas might make people of colour feel, we are driving said people away from the community and making it a very, very white space.