I built myself a cool one out of a retro 80s MTB frame and it does look quite snazzy if I do say so myself and every second stop a middle aged white dude either gives me the nod or straight up chats me up about it. This has never happened with my other bicycles, but it absolutely happened with my old singlespeed.
converted my one year old surly karate monkey to singlespeed one month ago, completely in love with the simplicity and the simple fact that at some paths/parts I can't simply go faster
using it for all mountain surfaces but downhill and also for commute, I'll not come back to gears
you can guess the age :)