When I used dating sites, seeing a guy's shirtless, muscled profile pic was always a turn off, if not a red flag in itself.

So bizarre that people would do that. When I was single and on social media and on dating websites (before smartphones), I did want to show off a bit that I worked out, but I had the discretion to, like, wear a T-shirt or a polo in the right lighting to show that I had strong looking forearms and a hint that there's something pretty solid under that shirt. Actually taking my shirt off would have felt way too desperate, and besides, just isn't something that I'd naturally have a picture of myself in.

Just seems to be a mix of validation-seeking insecurity and confidence in one's own muscles. Seems like a lot to unpack, and that combination probably doesn't really send a message that "becoming intimate with me is going to be a rewarding and fulfilling time."