Minnie Vans drop off/pick up in the bus depots.
Uber/Lyft do not. They use passenger pickup/drop off spots at each park. As mentioned, for MK this is at TTC
At Epcot, it's near the electric charging station, sort of behind the monorail and the grass area beside the monorail.
At HS, no idea. It is in flux due to construction. It used to be behind the bus depots but last I saw it had moved.
At AK, it's the best of all, right at the front, next to the tram stop. We take Uber to AK almost every time because it's the best spot