As contrast examples, I'd say unity is a no because "games" it's too broad, retool closer ("internal tools") but not really UX. Google forms very close, though not really considered dev infrastructure (or maybe it is?)
Can you help me think of companies that provide "UX infrastructure", ie tools / tech for making it easier to develop a specific type of user experience? (salesforce comes to mind for online retail, stripe for checkout, mapbox for maps)
Pretty sure we can make cursors a declarative part of the state chart, too. ie if a state has a custom cursor, show that cursor while the state is active. Child state cursors win over parent cursors.