I think it's problematic when a 40-year-old man claims to be an animal and starts acting like one.
But I have another way of looking at it when I see a child doing it, it's usually just a childish thing that doesn't last long, pretending to be a cat or a dog was already normal child's play even before furrys existed. Children enjoying their childhood
When you ask if a Satanist can be a "Therian", the answer is obvious
Jokes by young people who have no obligations.
Most of these videos are probably an inside joke.
There's no such thing as a therian in real life.
Such a high level of delusion is certainly non-existent, as anyone who had this ability must surely be dead and those who could have become descendants would never have existed.