Jeff, I hear, and I understand, your point of view.
I started playing in 1980. One of my players bought the Greyhawk Folio, then the boxed set, when that came out. I used that as our campaign world for three years. It was waaayyy too complicated for me to wrap my head around: so many nations were on the verge of war, and I could not commit them all to memory!
When I went off to college, I drew a map of my own campaign world, in 1983. I've been using the same world ever since. It started as a world map, then I realized it was really only one continent, not a whole world. I later drew in other continents, creating an Earth-sized world. I've only used one other continent, on a limited basis, focusing 30+ years on the one continent, where I based my campaigns, for four different player groups, 19 different players.
I know my campaign world -- I created it, from whole cloth. It is not fully documented, as most of it is in my head, and the heads of my players, alone. My players love it. They feel as if they own it, because they helped me develop it. It is not developed to a terribly high degree, as I only develop it as required by play. The adventuring areas are more highly developed, as the campaign demands. My players have adventured across 2/3's of this continent, over the past three decades, so it is highly developed, in my mind...
It has been a blast, for me, and for my players. It is a large part of the attraction for them, to my game: they've invested a great deal in the campaign world, and their PC's; they know it, they are familiar with it, and they own land in it. It is "home", to their PC's.
To me, that is one of the greatest achievements in my gaming career. It gives me great satisfaction to hear them take serious interest in what happens in my campaign world. They get angry when things go awry, and they work hard to set things straight. They are deeply invested in my campaign world. That, to me, is the greatest success I can achieve, as a DM, as a storyteller, and as a gamer. Cheers!