Personally, I have lived in big cities both with and without a car, and I would absolutely choose to keep my car and pay for parking if I moved back.
To state the obvious, people can want all the availability in the world, but they don't often get that because of the costs associated with it. Cars are expensive[1], and so is parking[2]. The costs of congestion are also typically only paid for by drivers with time (although many cities are toying with congestion pricing). Of course, the cost calculation for residents changes for different cities; the costs in Manhattan vs in Atlanta are very different.
So while you in particular may be able to afford the private cost burdens of car ownership, I believe the convenience of owning a car is a woefully inadequate metric to make policy decisions on. This is all mostly moot anyway as at least according to the original post, ridesharing does not positively impact car ownership.
[1]: https://www.hks.harvard.edu/publications/64-billion-massachu... [2]: The High Cost of Free Parking by Donald Shoup (ISBN: 1884829988)
Taxis should fit in there somewhere, but I've never used one because public transport was good enough, then when Uber/Lyft came about they hadn't yet come up with anything as convenient (or at least as well publicized).
But what cities are you talking about? In the Bay Area mass transit is absolutely not “highly available”. Nor in LA, nor in Atlanta, etc.
There is, to a rough approximation, one city in the US where you can get by without a car and not feel like you are severely restricted on schedule and destinations - NYC.
Between the cost of car ownership, parking, petrol and lost time for finding a parking spot we likely saved thousands in the 6 years we lived in the city. And had much better quality of live.
Edit: Also, valet parking is readily available in NYC, and very convenient.
The same happens with private jets. Yes, some first class seats are insanely luxurious. But you will never have the same experience as owning your own jet that you can hop on at a moments notice.
Well, sure. In general, being driven is better than driving. If money were no object, I would absolutely book a car service for a night in town rather than driving myself. But that would add about $300 to the evening--which I can afford but wouldn't pay just so I didn't need to drive.
Even in the best cases, any moderately popular place is going to involve a winding driving path and a moderate trek through a car park to get to where you actually want to be due to the inherent lack of density of cars.
In the worst case, there was a time when a group of 4 of us needed to go from the Mission to Alamo Square and one of us happened to have a car on us which involved a 15 minute drive and then a 30 minute circling of the block looking for parking which finally involved us finding a spot half the distance of just walking to the place we wanted to get to.