Porous ceramics can easily breed bacteria, good and bad. And glazes on ceramics can contain all kinds of delightful compounds that can leach out. You certainly don’t want to eat or breathe unfired glaze.
As for ceramic nonstick cookware, I’m not convinced that such a thing exists. I think that “ceramic” coatings are actually sol-gel, and I can’t find a straight answer as to what is in them. They do advertise that they are fluoropolymer-free, and they seem to be stable to rather higher temperatures than PTFE.
Ceramic glazes have been problematic [0].
[0] https://www.npr.org/sections/thesalt/2017/12/08/563808879/ca...
>Some PFAS are approved for use in the manufacture of non-stick cookware coatings. These coatings are made of molecules that are polymerized (i.e., joined together to form large molecules) and applied to the cookware through a heating process that tightly binds the polymer coating to the cookware. Studies show that this coating contains a negligible amount of PFAS capable of migrating to food
read this : https://en.wikipedia.org/wiki/GenX#Pollution
Florine is remarkably not inert.
Teflon is a relatively stable Florine compound.
But as you say, it can destabilize when the pan is used within a few sigma of ideal cooking temperature.