Yes, but also:

The metro area density of Tokyo is 3,000 / km^2

The metro area density of Beijing is 1,747 / km^2

Greater Los Angeles: 208 / km^2

LA proper seems to have a density of 3000/km^2 according to Wikipedia

A perhaps more interesting use case is the utsunomiya light rail. Utsunomiya has a density of around 1200/km^2.

What they ended up doing was building a new tram with exactly one line. The main thing they did was make sure the tram comes frequently, including off peak.

End result is people rely on the tram line and the tram is making good money, being operationally profitable (still gotta pay back construction costs of course).

Utsunomiya is obviously not exactly greater LA, but Utsunomiya has on average 2.25 cars per household[0]. It has traffic issues and people feel the need to own a car. And yet the tram line is finding success because transportation is a local issue, not a global one!

You can solve for transportation issues in crowded areas. Few reasonable people are lamenting that you don't have a train between madison, WI and Chicago every 15 minutes. Many are simply lamenting that even at a local level PT in many places is leaving a lot on the table despite there being chances of success!

Smaller focused PT has proven itself to work time and time again, and compounds on other PT projects in the area.

[0]: https://www.pref.tochigi.lg.jp/english/intro/overview.html