That's not what you said. Rims have been treated as just "a huge disc brake" since the inception of rim brakes because that's what they are. The brake pad material that has been developed for rim brake is optimized to provide a balance between longevity of the rim and the ability to stop the bike. With the exception of steel rims in wet conditions, rim brakes stop bikes just fine and don't wear out the rims at a rate that is too great.

I'd like to point out that disc rotors need to be replaced as well. There are limits to how much wear they take before they need to be replaced as well. Any friction system has wear involved and that wear needs to be addressed. The wear before replacement is in the range of 0.2 to 0.3mm which isn't all that easy to measure. Have you got something that can accurately measure 0.07"? Most people don't.