I agree that the focus shouldn't be solely on LGBT material, but there’s a strong public health case for giving disproportionate attention (not censorship) to MSM activity. The data consistently shows higher rates of STIs like HIV, syphilis, gonorrhea, etc in MSM populations. Targeting resources toward high-risk groups increases public health policy efficacy.
But as you point out, STIs aren’t confined to any one group, so focusing exclusively on MSM activity would be a mistake.
With respect to HIV, its prevalence among MSM is 20 to 30 times higher than in the general population.