A man who has an average to small penis AND feels insecure about it, probably shouldn't be here. Because no matter the intention behind the name lpsg, the reality is that praise for large cocks is everywhere in the site.
Do I give a shit? I give a shit about most things, in the sense that I find them curious and like to investigate.
I suspect so many gays like big dicks so much, because when being fucked by one, it pulls enough the skin that the tugging facilitates orgasm by indirect stimulating the prostate and cock of the fuckee. It can work for women, too. The tugging inside the vagina indirectly stimulating the clit by its skin being pulled.
Then there's the visual kick. People often think that big is better.
The fascination spills to 'straight' men. To the point some want their wives fucking big dick guys, so that they're (the men) closer to them (big dicks).
That's what I think, but I'm not 100% sure. I'm still investigating.