[danielhep]

Transit lines in many countries do support themselves by increasing productivity and tax revenue near the stations. It is not as direct as in Japan, where the train company itself captures the value created by its stations, but it’s effectively the same thing. Most places in the world with effective public transit systems are more like LA than Japan in how they are funded and operated.

[socalgal2]

The problem is they are almost always at the whim of politians. Take London.

https://www.google.com/search?q=is+the+london+tube+under+fun...

https://www.google.com/search?q=is+rome+subway+underfunded

https://www.google.com/search?q=is+barcelona+subway+underfun...

So you can claim, and I agree, that it's supposedly an investment. Unfortunately, putting it in the hands of politicians to fund often means funds are taken away for other things. Where as, the private Japanese train companies fund themselves and it works.