Not to forget, that most Watches are designed to be worn on the left side. (Position of the Buttons etc.) Smartwatches are improving here, in displaying a rotated screen, but often even these are asymmetrical designed and thus harder to use on the right arm.

I do as well. Even since I was a kid, wearing watches on the wrist of my non-dominant hand felt unnatural. I have no problem manipulating the strap or buttons on my watches.