My experience as a parent so far is that treating everyone beyond a whitelist of certified adults like toddlers works tremendously well.
Also there's the realisation that I've been effectively treated like one much more often than I would like to admit.
We might be saying the same thing, but one reason toddlers act so ridiculously is because they are emotionally responding just as an adult might, if they were treated like a toddler. Ie, “because I don’t think you have a valid internal POV, I’m going to just decide for you with no explanation”
This perspective comes from the book “how to talk so kids will listen and listen so kids will talk,” which is one of my favorite parenting books of all time.
I loved that book and tried to apply as much as possible to my own kid when she was little, now she's 5 and just lost her first baby tooth, I should probably read that book once again. One good thing about kids is that even if you make mistakes, you get plenty of opportunities to try different approaches and fix things.