I like Apple Notes, but collaborative editing is completely broken. I use it for sharing things like shopping lists with my wife. If I edit something while she's also editing, it gets mangled. Whatever Notes uses for collaborative syncing, it's not OT or CRDTs.

Notes is also quite terrible at many things:

* Embedded photos cannot be resized or placed next to text

* Table support is incredibly limited, to the point of being unusable except as a rudimentary grid

* No support for multiple columns

* No table of contents view

* No linking between notes (I think?)

* No way to change the font or change out the dreary yellow background colour

* No syntax highlighting of embedded code fragment

* No support for equations

* No support for shorthands (e.g. # to get a level 1 headline)

Notion, for all its flaws, has all of the above. And its collaborative editing is solid, if maybe not as good as Google Docs.