Waymos sometimes stop briefly in parking spots while waiting for assignments, but they don't really park as such except in special lots. The big problem I have seen is they tend not to always pull to the curb when releasing passengers and if a door is left even slightly ajar then they will sit there requesting the door be closed even if they are blocking a lane with many cars behind them beeping.
Not having a motor and thus having to depend on people to close doors on an autonomous car seems very silly.
Waymo's custom designed 6th generation vehicles[1] with self-closing doors were expected to enter service this year, but have [probably] been put on indefinite hold due to tariff issues
[1] https://waymo.com/blog/2021/12/expanding-our-waymo-one-fleet...
Minivans have had powered doors for decades and make great taxis, why do they need a special vehicle for this?
An earlier version of Waymo's vehicle was based on the Chrysler Pacifica. Like in a lot of areas, if you're going to spend billions of dollars to buy thousands of some product, it is worth customizing it for the specific purpose.