I've never heard the term Cali-Mex, but I'd say that Taco Bell is way closer to Tex-Mex than any other taco places in SoCal, which are generally much more authentic.
I appreciate many different cuisines, so I am not saying Tex-Mex is better than Cali-Mex, just that they’re different. Bringing Taco Bell into the equation and saying it’s representative is deeply insulting to Tex-Mex, however.