When I was a ride op, we used to be able to help guests. Then guests would try and drag us down when they fell, so we were told nope, we can’t help. Families then were able to help their own guests get on whatever ride. The wording is clear. You need to be able to walk from a mobility scooter or crutches or cane, unassisted to the ride vehicle.
I’m guessing universal wants to make it clear that you need to be able to be a little more independent than before.