Until you want more than the base fare ticket (reserved seat, green car, Shinkansen). I used the green ticket machines in those cases. That just works.

Takes 30 seconds in Apple Wallet to issue a new card and put an initial load on it. Don't understand what the problem is. Buy it before you depart, put 2000 yen on it with a visa/mastercard, get on the train at the airport.

This isn't so much an example of "Japan is wierd lol" but "you're tapping it wrong".