What's popular with kids and toddlers that's not Disney right now?
Octonauts, Gabby's Dollhouse, Paw Patrol (and spinoffs), Puffin Rock, Peppa Pig, Lucas the Spider on Netflix.
Cocomelon, Helper Cars, Little Angel, Blippi, and many unboxing videos on YouTubeKids. Actually YouTube has a lot of full episodes from other sources as well - it's my go-to for Octonauts, Peppa Pig, and Paw Patrol when I set my kids up on my 11yo Macbook that's too old to run Netflix. I suspect many of the videos I think of as being from YouTube actually have their own sites elsewhere (isn't Cocomelon owned by ABC?).
Disney is a very small part of my kids' viewing habits. Pretty much just use it for the Mickie Mouse and Bluey franchises.
PBS looks like it has some ok stuff
However, I did notice a number of times where my kids would have a harder time initially connecting with new social groups as there was less shared experience/context. They'd want to have some kind of make believe play where they'd assume a character from a show, but my kids had no context as to the expectations of the rest of the group and would struggle connecting. Its like the other kids were speaking a totally different language. Things would usually eventually work themselves out, but things could have been smoother and less stressful for my kids had they known the context.
Its like, back in the day, you'd be able to strike up a conversation with a someone and reference something from a show on one of the few TV stations, and there was a good chance the other person might have seen it and could get the reference. A shared experience, despite not being together at the time. Now days, good luck.
Explained here in a 1-hour video: https://youtu.be/rwhUpu9MfZ0