I thought building more lanes does not work. So why would building more lines work. Soon there will be induced demand and they will be even fuller.

Building more lanes does work - but people misunderstand induced demand. Really induced demand should be called fixing suppressed demand. If you get induced demand it means you need a lot more lanes. We can't afford the 50 layers of highway bridges needed to build enough lanes, but transit is a lot more space efficient and so we could afford it.

Because rail infra scales really well, bus infra scales well, and bike infra scales well -- while car infra scales disastrously.