Whatever had occurred to usher in the Younger Dryas has been more or less pinpointed to 12,800 years ago. Climate change was global and these people must have wondered if anyone would be left to tell their stories unless they left a reminder. Whatever else we know about these people, we know they were under considerable stress at the time, most likely having to forage more widely just to survive.
The video suggested they might be Animist in belief and that is likely the closest we'll ever get. Most likely it was a belief system that had sustained them for many thousands of years before Gobekli Teoe. I just don't accept the oldest part of the site as some sort of ritual site without any evidence of, well, ritual.
I made no allusion to human sacrifice, only to sacrifice, which might have been an animal they were going to eat later, ritually killed, or even plant foodstuffs burned as an offering. So far, evidence of either is lacking. We just see bones left over from food they brought with them on their visit.
As for men and their plumbing, that's their problem. They eventually discover they also have a prostate and are a little less liable to endow the rest with godlike qualities. However, I do see this as a men's site with the exclusively male imagery and preponderance of animals they'd have been wary of as big game hunters, which we know they were.
Oh, and PAINT, they had to have PAINT or it would have been pretty unimpressive, no matter the light source. We find the oldest stones impressive because they are beautifully carved and because they are so fantastically old.