That change in emphasis made all the difference. If done properly, it will clarify what the real spending needs are. These could all have some bearing on a variety of problems, including greenhouse gas emissions or other pollutants. The fees would encourage individual members of the public to get more certain about what their real needs are, and stop unnecessarily wasteful uses from being subsidized by the general taxpayer. People still get to make their own choices and are better able to balance their needs without more cumbersome governmental involvement.
Businesses are free to respond to the changing markets.
If the general fund taxpayer is paying for the system, then drivers feel no pocketbook incentive to use the public good, i.e., road system, conscientiously. So, focus first on the manner in which funds are actually raised. In a way, this fiscal strategy isn't such a big change. Drivers, until recent decades, have always paid for new road capacity via gas taxes. Those needs would only exist if taxpayers continued to subsidize car drivers, artificially spiking demand.