Donald Ducking to and from the beach
My minimalist approach to visiting the beach often sees me heading there with just my cap, a long polo and perhaps a swimsuit. The length of the polo just allows me to get away with not wearing my swimsuit. Since I'm a grower and not a shower, and since my scrotum tends to go compact in the open air, I have just enough length to stay covered as long as I don't do anything but adopt a slight slouch as I walk. Should stand straighter or reach up my cover is exposed. There's a little bobbing around beneath my shirt, but I don't think it too bad.
I've gotten quite comfortable walking like this, even on one of Australia's busiest coastal walks.
Let's see if I can illustrate the situation:
The other day, I headed out in the heat of the day and, as would be obvious to but anyone but me, that makes things relax. A bit more risky, at least until everything shrunk back a little but I continued on.
I couldn't resist using my camera to gauge the additional risk. Beae in mind the camera is about level with the hem of my shirt; most eyeballs are higher up. Still, the amount of sag had me a little concerned.
If I do have a suit on, I don't have to worry about slouching as everything's covered, unless I'm in a thong and then my checks may become exposed if I reach really high or bend over to use a drinking fountain. The back of my shirt is slightly longer than the front so it is less of a risk and anyway, there's at least one partially-bare pert female butt every five metres or so around here. I take a little care as I know I don't have a pert female butt to show off.
This clip shows my orange thong. At the start I'm standing quite straight and towards the end my posture is more neutral.
I think you are quite safe as shown. I have walked around the neighborhood in just a shirt many times. Since most eyes are above the hemline and you are constantly moving, it makes one wonder if he had anything on there.
It is a bit more obvious if I have my rings on - that's what started me thinking about this topic. With rings, they have a push-out effect and there's a lot more movement to encourage the hem to lift more and possibly not even fall back. Still did it, but it did amplify the daring on what I imagine could be Australia's busiest coastal trail.