Yeahbut dockless hire is currently knobbling the footway's functionality. That needs to be dealt with, otherwise the hire scheme will (rightly) get shut down.
In the particular case of central Birmingham it's pretty much a non-issue: The city centre is small enough that most things are a short walk from each other, while being utterly impenetrable to law-abiding wheeled vehicle users, on account of a proliferation of pedestrianised areas[1], tram tracks, anti-terrorism barriers and one-way streets that all lead to the inner ring road[2]. The use-case isn't that you use a scooter to get around the city centre, so much as in and out of it.
Voi appear to have distributed the docks I posted a photo of a couple of pages back around the city centre, and may have geo-fenced other suitable areas for parking without physical docks. Looking on the app, there's a typical-for-docked-bike-hire distribution of parking areas in the more accessible parts of the city. Which makes them about as useful as Boris (or indeed Beryl) Bikes; if there isn't a nearby dock, you walk. Hire schemes were never going to be door-to-door the way owning your own bike or scooter would be. At best, a dockless scheme tends to be somewhere-a-short-walk-away-to-door, and a docked scheme is short-walk-away to short-walk-away, like public transport.
[1] These are legal, and sometimes necessary, to cycle on. But not exactly fun, on account of dense foot traffic. The Voi scooters' speed limiting kicks in when you enter them.
[2] For those not familiar with Birmingham, picture the sort of 1960s car-centric concrete monstrosity that comes to mind when someone says 'Birmingham'.