Your observations are quite correct. The other week a strong gust of wind blew my skirt right up as I was walking down the street and I felt incredibly embarassed. However, I can walk along a nude beach utterly naked except for a sunhat and sunglasses rather enjoying the way people look at me. I guess there is something about clothing and modesty that we never really grow out of, as well as expectation. A naked man or woman on a clothing optional beach is perfectly normal, while the sight of my pink panties on Main Street is inappropriate.
As far as looking at men is concerned, I rather like beachwear small and tight -- and I confess when dressed and in social situations checking out a man's crotch.
It all depends on the venue and the company you're among. I have just about zero modesty. I'm perfectly comfortable being naked in front of other people who don't mind seeing me naked, but in Amish country, I can't even go braless without feeling self-conscious. It's about how the people around you react to the way you dress.
I agree with Beffer. My penchant for being nude would be most embarrassing to me and others in Syria. I could not bear to wear that uncomfortable clothing that is required there. I think I would end up being stoned to death.
As a nude model some years ago, I can be uncomfortable if seen in my underwear when I am not expecting it. I use my inadequate hands to cover virtually nothing until I realise who is looking.
As for a bikini, thong etc, no matter what type, you deliberately set out to expose as much fleash as you desire to be seen and hope to be admired. I am more than comfortable naked and provided I am not being perved upon I am happy for people to admire my naked body and see how I am built and my attributes.
As for men, shorts or swimmers are preferred by me. I hate seeing men in budgie smugglers. They are attempting to tease us with a display of their size of their genetals, and size does not matter to me. I have seen some I know boosted by padding to impress I know not who - pehaps other guys as the woman I know are certainly not - unless it is in the bedroom..
For me it comes down to choice and being in control.
I'm a naturist, I'm a lifelong member of a naturist club and I am very comfortable being naked in front of other people in this setting, at other clubs, beaches...
If however someone walked in on me changing/ naked/ my skirt blew up etc. then I wouldn't be as happy.
If I choose to be naked then that's fine, I've opted that anyone can look. Whereas someone catching a glimpse feels like I'm not in control of the situation, like I've been taken advantage of or stripped of my freedom.