There’s lots of ways to approach defining a ‘reasonable’ equilibrium. You could set a target for average time spent communing, but to address a problem like the one described in the article, you’d just need to build enough freeways to ensure that using a freeway is on average faster than winding through suburban streets.

You could do this by decreasing the efficiency of the non-freeway roads, or increasing the cost of using the roads, which both only ‘solve’ the problem by reducing general quality of life (especially for poorer people, who might just get even poorer if they can’t commute affordably).

Or you can increase road capacity to keep up with population growth, and invest in alternative transport that people actually want to use. That means no cycle lanes or buses, because people really don’t want to use them (buses are only really efficient for short trips, if you have to change buses to get to work then it ends up taking so long you may as well just be inefficiently sitting in the comfort of your own car).