Plenty of black people in San Diego, just probably not as many as Houston.
The problem is that most black people unfortunately live in undesirable neighborhoods (i know that sounds

but I’m a native been here my whole life)
The GOAT thing about that is you can get a nice spot in a black neighborhood for less, but not really too much to do in the areas. Spring Valley, Lemon Grove, National City, pretty much anywhere in Southeast SD you can find affordable living, but you won’t be doing much in the area.
If you move here move downtown, Cortez Hill area. Decent costs but close to the city. HMU if you have any questions

and I know
@Brolic Scholar is here too