Never had a problem cleaning / maintaining my bores in like factory new condition for over 20 years now, so the rotating handle thing is a complete non-issue to muzzleloading.
Worse, rotating handles eliminate the ability to use other ramrod attachments which require positive single direction torque to be applied, ie: using a breech face scraper, using a ball puller, etc.
There is no bore wear with any good stiff, strong rods using good quality muzzle guides. The only other way bore wear could possibly develop would be if using a noodle-limber rod that might bow in the middle or something and I can't imagine how many years that would take to develop.
Brass and anodized aluminum rods are stiff & strong, and in fact, these smaller diameter 5/16" anodized aluminum rods actually seem stiffer than the 5/16" solid brass rods I already have.
Rotating handles evolved for modern centerfire rifles, not muzzleloaders.