I'm guessing Philly and Baltimore are his idea of "East Coast accents that aren't as obvious as New York or Boston".
The San Francisco accent definitely still exists - I have it - but, being blunt, you gotta be white. It's similar to Boston, New York, Philly, and New Orleans in the sense that it's the sound you get when you stuck Irish, Italians, Germans, a handful of Eastern Europeans, all Catholics, and some Jews and blacks. You adjust the ratios a bit - SF's rather light on Jews, for example - but they all sound like they come from the same family.
I'm not sure where the Chinese community (much less the Latino community) comes into this, but I sound more like
Angela Alioto than
Cher Horowitz.
Interestingly a lot of Asian friends I know, most of whom are first or second generation immigrants, sound way more "Valley".
Edit: You know what SF sounds like? People from the larger towns of southern Connecticut. A lot of people think my parents are natives, and southern CT has exactly that mix I described above.