Yes, but they don’t typically have any continuity with each other, and, I’d assume, especially not with KH.
Fair enough, but as the Disney Castle/Town and characters from there act more cartoony, they could rely on cartoon login, which in many cases (including Mickey & friends characters themselves) include ambiguous or nonexistent aging rules.
Plus, even if different worlds have time work differently, the 12-ish years between BBS and KH3 should've been enough for Donald's nephews to age at least a tiny bit, yet all that changed is their models matching kh3's graphics.
I'm not saying you're wrong, and your side makes sense, but I just like the idea of their world and characters not aging better. It reflects what the world was based on, which is silly, ridiculous cartoons that don't need real-world logic to be great. That's just my two cents.