[kewrkewm53]

Unfortunately for many people increasing the expense will simply leave them without any alternatives, which isn't a good thing either.

Think of a low-paid European worker who commutes to work inthe countryside where public transport does not work. Increase cost of commute enough, and it will make more sense for that person to live off welfare than go to work, especially if the salary isn't sufficient to afford same quality of housing closer to workplace. Not good for the economy.

A future without cars works only if we either heavily subsidize public transport in rural areas, or force everyone to live in tightly-built cities full of tiny apartments where quality of life is always going to be inferior.

[dredmorbius]

My point is that expense has been rising, and both use (passenger-miles driven) and ownership (vehicles owned percapita) have plateaued or fallen across much of the U.S. over the past 2+ decades. That's already shown in the statistics.

The effect isn't uniform by region, and is most pronounced in cities. New York has never had high car ownership, and IIRC it's fallen elsewhere, notably San Francisco.

You obviously don't want these increases to occurr suddenly, or without any compensatory changes --- improvements in transit, changes to land-use, alternatives such as bicycles (for the healthy) or paratransit or rideshare or deliveries (for the disabled). Sudden hikes give rise to protest (see the gilets jaunes (yellow vests) protests in France. But phased over the course of a few decades, and with the land-use and density changes that are needed to support this, as well as changes to basic wages/income, and pensions, the effects could be quite pronounced.

But in tandem, increase costs (both monetary and hassle) of private car ownership and enabling of alternative transport, would be far more effective than either side of that alone. In economics: raise prices, lower consumptive usage (in most cases).