I think one of the biggest things, besides not being owned by WOTC, is that it doesn't have a million exceptions you have to remember.

D&D5e: Want to use your bonus action? Cool. Is it for a spell? Have you cast a spell this round? Is it a spell that's allowed to be cast even if you've cast a spell?

Pathfinder2e: Do you have enough actions to perform an action? OK, do it.