Irvine is not part of LA's public transportation system...
And in the case of London and Berlin, you're comparing national rail systems to that of a single city that could easily fit the 4 cities you mentioned within its borders and still have room for Paris and Tokyo. And let's not even get started on the LA metropolitan area, which is geographically the largest in the Western world.
Irvine is about as far out as Mandurah from Perth and it goes about that far again north: if LA's public transport system was actually well designed it would be.
And in the case of London and Berlin, you're comparing national rail systems to that of a single city that could easily fit the 4 cities you mentioned within its borders and still have room for Paris and Tokyo. And let's not even get started on the LA metropolitan area, which is geographically the largest in the Western world.