As a married man, completely straight, I am all for the Speedo swimwear: in a private pool, public pool, beach, hotel pool… you name it. However, I do not own a speedo, though I feel completely comfortable wearing my briefs. They are briefs without the Y in front. I have come to the belief people think they are Speedos.
If I see other men wearing them, which I have yet to, I would understand and not give a damn. They are comfortable and I am confident with myself wearing them. I am not muscular, but a fairly thin dude, secretly hoping people are grabbing a glance of my bulge. Men / women can have all the looks they want, and I hope they do. My wife is the only one for me though.