Arts organizations have often struggled to draw diverse audiences, and it can be even more difficult to achieve true diversity within the ranks of performers and managers. Ordinarily, this is one of those problems that everyone talks about from time to time without really doing anything to solve it. But in San Diego, where the city takes the diversity of an arts organization into account when divvying up available funds, the lack of ethnic and racial diversity on area arts boards is becoming a big financial problem, particularly for the city’s celebrated Old Globe Theatre.