beneful1 saidOff the shelf pants are usually tailored / cut with a little bit of extra room on the left side which is why placing your stuff over on the right side doesn't feel quite right regardless of which way you normally hang.
When you have custom made pants you choose which side you want "fitted" to
Is that sort of irrelevant if you wear briefs/trunks?
True, not relevant if you wear snug briefs.
I remember when I was 14 and about to attend prep school. My father took me to his personal tailor to have my suits made, since we would always be wearing our own business suits to school, not the uniforms I'd had previously in K thru 8.
So this is 1963, and I'm standing on a little carpeted platform, with full-length mirrors all around, as the tailor is measuring me. My Father was sitting in an armchair nearby.
The tailor ran his tape measure up my inseam and tapped my balls with his hand.
"On which side do you dress, sir?" he asked me.
On what side do I WHAT???
I panicked for a moment, not sure what he meant. But then I figured it out in a flash, and replied: "Neither, I wear Jockey shorts." Tighty-whities we'd say today.
And so he made my trouser legs symmetrical, without any biased allowance for my stuff hanging down one leg or the other due to boxers.
Such tailoring considerations are likely unknown today with most men. In fact, who even tailors? You buy off the rack, end of story. And you hang where you hang, if you hang at all. Under dress trousers I still wear briefs, and avoid the issue altogether.