Methanol is only ever a tiny portion of the fermented output and that's only with grain fermentation. There's nowhere near enough to blind anyone. Fruit or sugar fermentation does not produce any methanol. In that case the unwanted contaminate is ethyl acetate, which is less harmful but still ruins the drink. It gives bad whiskey its burn and causes hangovers.
In both cases the procedure is the same: run the still very slowly at first to increase reflux, pulling off the "foreshots" until contaminants are gone. In the process the still head temps will stabilize as the various low boiling trace compounds are eliminated.
Then one runs the still at a normal rate, collecting heads, middle, and tails, and blending those according to one's skill to get the desired product.
The middle jars are the clearest and cleanest alcohol, but the heads and to an extent tails contain aspects of the flavor and lots of good alcohol. Whatever isn't used for final blending will be collected and recycled back through the still in the next batch.
Properly distilled moonshine is very clean and smooth, like drinking water. No burn and no hangover. If it burns the tongue or gives a hangover, that's because it was not distilled to the highest standards. Most commercially available alcohol isn't.
Badly distilled moonshine is 100% a product of prohibition and would not exist for long in a free market, because drinkers won't tolerate it.