I would venture, insular communities and bad luck. Maybe also something to do with cultural mores around visiting family when sick, or insufficient "how to mask/distance/etc" materials in Spanish.

I think it's like Gay-Related Immune Deficiency (GRID, before it was AIDS). There's no inherent reason that it showed up predominantly in the gay male population, except a) the first superspreader was a gay airline steward (so he had lots of contacts with the gay community all over the country), and b) gay men were enjoying the fruits of their sexual revolution.

If you think about it, monogamy is basically an extreme form of "sexual distancing", and so a non-monogamous community is much more likely to have an outbreak of an STD. Other non-monogamous communities heavily promote wearing masks (condoms), but as this had been viewed primarily as a way to prevent pregnancy, the gay community did not think it was necessary.

I think it's just because hispanic people are poorer and thus more likely to be essential workers.

In SF, I've heard that a good percentage of the latin population will share rent-controlled places 12 to a room. I think it's more common they are living in tight quarters.

Overcrowding. Multiple families sharing apartments is typical of low income areas in CA.