Actually AI also benefits from thins being organized. I find Skills to be Zettlekasten inspired or wiki inspired in that sense.

Zettlekast has other benefits for humans though. If your goal is to grasp lot of knowladge oyu need to do it in atomic way, connect mentally to what you already know and do spaced repetition to internalize. Zettlkeaste forces you do it it all as part of organizing. Basically by organizing you make it your own.

Yes AI can help today but it also means it does not stay in your head. Not sure its important if it is in your head or you can call AI at any moment instead of your own memory.