Very conveniently glossing over the fact that if are developing for the Mac, no you don't. You can distribute it outside the store without paying anything.
iOS, yep you're right.
iOS, yep you're right.
Considering it would take less than a day for Apple's registration scheme to be overrun with billions of fake app builders if they don't put in a small monetary roadblock I don't see how this situation could be improved.
I think this is fine. If you're a business, the developer fee is not a significant expense, and it makes the whole ecosystem work smoothly. If you're a hobbyist, student, open source developer, or otherwise in a position where you won't make that money back quickly, macOS provides a workaround for opening unsigned apps. This is so different from the terrible situation on iOS.