>>1193189Hackshually, since the Pacific Electric was an interurban streetcar-type service, it was relatively cheap to build and operate (compared to proper heavy rail), so it didn't need very dense development to be sustained. Also the type of streetcar suburbs that it fostered were still denser than modern car-based sprawl.
The Pacific Electric's main problem never was a lack of ridership. Even all the way into the 50's it had decent patronage. Its problems were
a) massively subsidized highway construction parallel to its own lines
b) traffic slowing down its trains (especially downtown) and of course
c) being actively shut down by NCL (through Metropolitan Coach Lines which was presided by a former Pacific City Lines exec, PCL in turn being a subsidiary of NCL)
Post-war ridership on the PE was even good enough that they bought some brand new PCC streetcars in the late 1940's.
The Pacific Electric is a rare case of a streetcar system which through ridership and popular support would have been able to keep sustaining at least a large part of the network. A similar example is San Francisco's Muni, which actually did keep some streetcar lines.