I hated underwear when I was a kid, with a vengeance, and I still do; my mother was cool enough to not force me to wear any, although she didn't like it. At sixty six years of age I still don't wear it, 'going commando' is,
I think, the phrase for it. I never have any problems with hygeine, nor do I have problems with persiration and none at all with chafing. I've walked a minimum of six miles a day for many years and often do twice that, I ride horses a good deal (and I don't mean happy hacking!) and I've never had occasion to even be conscious of the fact that I haven't got keks on.
I wear underwear for hospital and doctors appointments and sometimes my partner expresses a wish for me to wear it for some special occasions as she sometimes just becomes conscious of it, but whenever I do wear any I feel wrapped up and restricted and extremely uncomfortable.
Give it a try, it's a whole new world of freedom!