I don't run MacOS anymore but based off the comments it sounds like the window snapping is not that great yet. Makes me wonder, why not just buy Magnet or one of the many other apps that do this and integrate the source into MacOS.
Current approach sounds best to me, Apple gets to implement a (relatively simple) feature exactly how they want, power users and existing users can rely on third party apps.
Probably because it costs like 10k per line of code for apple to implement anything decent. (not claiming that magnet is decent)
The only snapping features I use are snap left, snap right, and resize both snapped windows at the same time (which Rectangle doesn’t do).
Sometimes less is more, I’m more happy with Sequoia native snapping than with Rectangle/Magnet