There's also all of the service vehicles when you get closer to the gates. The likely damage from an incident during taxiing is much less than during take off or landing, but I think the risk of having an incident is higher and the situation is trickier to manage. And it's super doable to have a pilot come on to manage that, and drop off after the hard part; you couldn't reasonably have pilots do a takeoff and then jetpack over to an arriving plane to do the landing, but it wouldn't be unreasonable for ground moves... similar to canal pilots taking ships through canals.