The theory of induced demand says that increasing the amount of roads/lanes available increases the amount of driving - not necessarily of congestion (which implies driving at slower speeds).
In areas that are basically entirely car-dependent, the implication is that more roads encourage more journeys, and that fewer roads result in more journeys not taken. It's unclear why persuading people not to travel is inherently a good thing. Presumably they're going somewhere to see people and do things.
Perhaps building new roads doesn't help them do that any faster, but there are more people getting to do the things that they want.
In areas that are basically entirely car-dependent, the implication is that more roads encourage more journeys, and that fewer roads result in more journeys not taken. It's unclear why persuading people not to travel is inherently a good thing. Presumably they're going somewhere to see people and do things.
Perhaps building new roads doesn't help them do that any faster, but there are more people getting to do the things that they want.