Frankly, the whole "Low Magic" thing smacks of grognards looking down their collective noses. "Oh, that FR is alright for the kiddies, it's high magic after all, for those of us with taste, though, it's just gauche". It ignores the fact that Greyhawk most certainly isn't a low magic setting at all. Good grief. You have commoners with magic swords in Hommlet. Actually, looking at any GH example of a town or village, there are multiple magic items in the town, as well as multiple casters, frequently of fairly significant level. Magic was by no means rare or unheard of in the setting.
But, because FR is "high magic", then Greyhawk MUST BE low magic. After all, some folks want Greyhawk to be different and are desperate to throw up any difference they can grasp, even though it completely contradicts the setting itself.
I'm sorry, but, it's laughable that in a setting where you have countries governed by actual GODS, that it's a low magic setting? Where there are artifacts all over the place? Heck, where any given treasure trove had about a 1 in 10 chance of multiple magic items? I mean, how much magic do you need to make something high magic?