You're right it does not help in the short term, but we've been speaking about the Bay Area problems (for example) for two decades and vigorously discussing it

You're right it does not help in the short term, but we've been speaking about the Bay Area problems (for example) for two decades and vigorously discussing it in the past decade -- building five years ago could have solved today's problem. Similarly, we could speak about it for another decade, or we could build now and solve part of the problem in five years. This also doesn't exclude other fixes that can happen orthogonally.