Bourbaki school of thought. Read Dieudonné - not a single( I think to remember) illustration. Kindergarten starts math education with set theory. This was the imaginated ideal.
Ironically, her independence from ZF would make the classical Bourbaki group shiver. The same way the earlier, better known, work of Goedel did.
I don't know, if you are aware of Bourbakis spirit. There is something much more important in this context as the content-wise difference between sets and numbers. I never would argue against applying naive set definitions in a suiting way. But Bourbaki had an agenda, and this agenda is not for everyone (certainly not for me).
Well what’s wrong with that?