People are going to cling to their cars until they have a viable substitute that offers all of the following:
1. Psychological safety - that they wont be robbed or assaulted, wont have to encounter people they dont want to, wont be uncomfortable temperature wise, wont be late due to unreliable operation (including the apathy of unionized workers), wont have to smell things they dont want to smell
2. Similar experience to cars - Get them within 1/4 mile of their destination (~5 minute walk). Anything more means adapting fashion to the elements.
3. Does not have seasonal variability in usability - The bus in Calgary, AB is amazing in the winter, and sucks in the winter (waiting for a late bus in the cold means you have to dress for 40 minutes in -20c weather, when it might only be 2. And then you're inside a 20C bus with far too much clothes on. And it's hard to end up at work presentable. This is probably far less important now with rise of remote work for many.
4. Is not a tax line item that is absurdly expensive per user mile. Right now a lot of public transit is under utilized meaning it's actual price per user mile is very high. I get that it's a chicken / egg challenge. How do you get people to use a sparse system unless you build out a full suite of routes. How do you build a full suite of routes without having them be underutilized, at least at first?
5. Works 24/7 for their needs.
6. Works well for families. Getting groceries with 2 kids, going to urgent care acceptably fast, pickup and drop off at 2 different schools (elementary / middle for example). All sorts of patterns that work with 1 parent and 2 kids each having a diff destination.
Ultimately I think with autonomous cars the whole landscape will change rapidly if the gov't & unions allow it. Parking isn't an issue if my car goes home to my garage during the day (or can park itself within an inch of the next car because no one is getting in/out and the cars can coordinate to unblock each other in a truly packed parking garage). Even more so if the autonomous car is not mine and it simply goes to pickup another rider. Now we have controlled environment for just me and the car can be a small 2 seater like a smart car.