Probably a rather small deal at that age, and completely innocent as well.It shouldn't be a big deal. I remember having erections, very hard ones at that, when I was 5 or 6.
When a five or six year old has one, even a very hard one (seriously?), it's not going to offend anyone -- when a fifty-five or six year old sprouts up at a nude public spot and just smiles about it, the man's intentions - as in why it is being left on display - will be questioned by the parents who see him stiffened up near their little ones playing in the surf, dontcha think? What family social nudists have against erections left out and throbbing is when a guy thinks it's a god-given right for him to show off his proud peter wherever and whenever it comes to visit. So thanks in advance for understanding that such thickening occasions need to include a towel to pull over it, or at least turn the fuck over, so the families don't have to bear witness to that inappropriate perpendicularity.
Next time, consider flogging the dolphin a couple of times before a trip to the nude beach. They don't call it "going off half-cocked" for nothing! Rub that bottle and uncork the genie at home first ~ do everyone at the beach a teeny-weenie favor. Fifty years of that thing hanging down between the legs should've taught the owner a few valuable lessons.
It all depends on the time of environment. Like in a family environment I would say it would be inappropriate to display an erection in front of mixed company. Age is big factor too. Young adults and boys should have a pass but they shouldn't flaunt their erection either. As a lad growing up nudist with my old man, he made it very comfortable for me not to feel ashamed nor embarrassed because I popped a boner for no reason.
Just a quick thought: I enjoy seeing all the diversity of male bodies in particular and penis and balls in all states - this is part of the joy of social nudity. In fact it would be nice to see more erections as I think there are too few to be seen. Maybe some nude gatherings should focus on erections to correct this imbalance.
Well been a naked Male all my life- family were and still are farming/ranching. Boys and boners were no crazy assault on the rest of the folks, elders, neighbor join at the pond after a hot day's work in Illinois. It was seen as, "ALL THINGS WILL PASS" and they did. I saw my father erect so many times it was boring- brother too since when dad needs to get to duty and my brother and I needed to get to school, all three in the larger of two bathrooms to give my mother her own, you see dicks in all stages at 6am! LOL!!! And in the Army in the gang showers with 80+ young Males showering, no sex for weeks, YOU SEE BONERS!. It must be nice to stop the world and jump off till your loins settle down, but explain that one to your drill SGT! "Excuse me Sgt, can we start training when I can get dressed and walk straight?" yah right LOL!!! And after the past 4 years, the Male genitals are now "toxic",. No you say? well then why do the gals, and now the guys call a Males genitals JUNK. Mine is not JUNK, tho there may be some credence to the term seeing what is being produced by certain factions of our population. 68yo now and no issues enjoying mine and should I be awarded with a big one in nude public, I know where the dep end of the pool is-grin, but when I am 80+ years old poolside and my penis rises to the occasion from a very vivid imagination, like that 25yo gal that keeps staring at me really WANTS ME!,...., they better throw me a party right there and then.
But seriously- well a different direction, erections show health and vitality, but the guys walking around showing it off should be told to cool it, WHEN children do see an excited male, it should be a healthy- a no "big" deal thing. Not a STOP THE PRESS happening. You make a huge deal about it- your child will too, oh and tell ALL the neighbors how big his daddy is,..., or isn't! HOOOOT!