alt Hacker NewsI was a transfer to UCSD - the transfer community itself is pretty large and one college (Sixth) houses a significant percentage, with dorms specifically for transfers. IMO there was far higher interesting diversity of folks there compared to rest of campus: veterans, addicts who got their shit together, tons of immigrants who couldn't afford going straight to UC (as well as your standard mostly 20-22 year old SoCal transfers) from which most people I know formed good networks.
Sure, there's a community either way. But how does the CC -> UCSD transfer community stack up against either (1) four years at UCSD (which OP would say not to go to without a full ride) or (2) two years at UCI and two years at UCSC or UCLA?
My guess is that there are hardworking people in both groups, but the ones who start out at a four year institution are more likely to be tip-top, and to have family/friends who would be valuable in a business network years down the road.
This is somewhat less true now that UCs are pushing to admit so many LCFF students, but I think it's still true in general.