I think one reason they make "ML scopes" is that the use and characteristics desired by the market are somewhat different than for centerfire scopes. Shotgun scopes as well but there is a recoil issue with shotguns too.

I don't completely discount that some scopes will not hold up as well on a ML but I've been using rifle scopes since I started mounting scopes and have only had one scope crap out...and it was the only ML scope I've ever owned!

Each gun has its own harmonics, I guess I'd need to hear some rational evidence how a ML and a centerfire throwing a similar charge at a similar velocity would impact a scope in a different way, and specific design differences that must be put into a scope to account for this.

I will say that the loads most people shoot in a ML generate more recoil than a .223 or .308, the recoil level where most rifle scopes play. Perhaps that has something to do with it. That's how shotgun scopes are different, they are made to tolerate way higher recoil generated by slugs.

Airguns are a different story. Due to their piston action there is a two-direction recoil very different from powder-operated guns.