Yep. Apparently this was a thing last summer. I missed it because the press was busy promoting peaceful protests so no doubt didn't have time to look at this kerfuffle. The excuse from the clip's creator is that it aired on Adult Swim, the adult oriented time slot on Cartoon Network. It wasn't shown during kiddie hour.
I say imagine if the babies were black. Or imagine if they were in some way portrayed as a designated minority group.
Most edgy leftists have stones the size of neutrons when it comes to who they are willing to offend. Let them go after a couple old ladies in a country church, and they act like they're as brave as Superman. Suggest they go after Muslims, or BLM, or the LGBTQ movement, or China, and expect to see them do their Dr. Smith from Lost in Space impersonation.
As for the content, I'm sure it speaks for itself. A reminder that all the evils of a pagan world didn't suddenly vanish because we thought we had moved on from a pagan world. In fact, you might say the modern Left is very conservative, just itching to go back to a pre-Christian paganism and all its glories.