EV shuttles will come in lots of capacities. Vans, buses. But you won't need to worry about schedules or preset routes because it's all dynamic.

Wherever there would be the most congestion is precisely where the app will give you the biggest discount to switch from your private vehicle into a bus, then switch back into another private vehicle for the last 5 minutes of your trip.

They can go into cheap, boring tunnels (little ventilation requirements)

I was thinking autonomy, but you're right for EV alone.