The way I look at it, as the laws are written, the existing technology establishes the baseline for the equipment, and you can do anything you want so long as it is within the law, and your personal capabilities.
Many people with superior eyesight and athletic abilities can actually shoot iron sights better than they do optical ones, but the majority of us do not. If we choose to hunt with a stick bow during rifle season we certainly can do that, but we have voluntarily handicapped ourselves relative to the average hunter out there with modern firearms. The same is true if we choose to hunt with a traditional ML'er. We're less handicapped than with a bow, but still handicapped relative to more modern equipment.
Once the gun is loaded, it really isn't (functionally) that much different than a modern single-shot gun, save for the constraints of the propellant and projectile. There are people out there (and there used to be a commercial company) that make muzzle loaders designed to fire smokeless powder, so even those limitations are neutered.
Once a technology that gives you an advantage is invented, it's usually pretty expensive, hence, not common. Only super techie or rich guys would use it. Take night and thermal imaging equipment for instance. 30 years ago It cost $4000-$5000+ for that stuff. Nobody had it so no game laws were written to limit the use. Now it's <$1000, and much more commonly owned, so laws were written to limit its' use, and keep things "sporting" for the game. Subsistence hunters don't care that much about game laws anyway, so they are always going to be operating outside the law.