AITAH for asking to take down a social media post

Ok so my kids dad gets him every other weekend. I’m ok with dad, but his family is always a problem. They posted a cute compilation video of my son on Facebook and I was watching the video bc that’s my baby, and then several pictures came across of my son and his cousin, on a blanket that says “Nazi Friend” and “Demo Nazi”. I asked dad to please ask them to either take those photos out of the slideshow or blur the words..bc wtf? I also asked for context about what is this blanket? They said a friend made it for them to them it means fierce protector and the whole blanket says “gym Nazi” and other descriptors. While I don’t agree with the blankets existence, I can’t do anything about that, the internet doesn’t care in my opinion about the context, and I don’t want my kid associated. They still have not taken it down after asking several times and I don’t think they will as they’ve basically called me woke and don’t see why I don’t want it out there. Am I the asshole for trying to tell them what is appropriate to post? I normally would never but only bc it’s my kid involved. Thoughts?