Yes, that was a description of the nude section. The vast majority (98%+) were fully nude. I saw a few women with bottoms. The volleyball players were mostly clothed.

Male/Female ratios varied dramatically depending on where you were on the beach. On the north end, it was over 90% all male, and most of them appeared to be couples (only walked past, didn't stay there). In the middle section, it was mostly male/female couples, of all ages, though generally skewing toward seniors. In the section, there were a number of single males, "roosters", strutting around.

I didn't make it down the to south end, but some regulars described that there is a section of primarily latino/cuban americans, and then a section of primarily african americans. Self segregation, apparently.

I didn't notice anything "perverse". I do suspect that the weekdays will be slower and generally older, so the "dirty old perverts" meme may be from weekdays.