I've been re-listening to some Geek's Guide to the Galaxy podcasts at the gym, and the one I had on today featured Orson Scott Card holding forth on a wide variety of things. (If you've never heard Orson Scott Card giving an interview I recommend you do so: he's good value.)
One of the things he said was that for a very long time fantasy literature was crap, because too many people simply aped Tolkien without understanding Tolkien's genius, or his message - which was not "do what I do" in the sense of creating fantasy worlds full of elves, orcs, hobbits and world-saving quests, but "do what I do" in the sense of creating fantasy worlds that feel real. People looked at The Lord of the Rings and took from it exactly the wrong things - the window dressing - without understanding that the real magic of Tolkien's work was the creation of a genuine secondary world. Instead of providing carbon copies of Middle Earth, they should have done what he had done, which was to create something of their own.
Likewise, when William Gibson was in his pomp around the time his first loose trilogy was being published, Bruce Sterling made a plea for science fiction writers to follow him. What Sterling had meant was that he wanted writers to follow Gibson in creating well thought-out, fleshed out, deep-feeling settings and stories. Instead, loads of people just started writing stories with Gibson window dressing - mirror shades and cyberspace and noir. This resulted in what Card calls one of the most pathetic literary movements ever, Cyberpunk, and I'm inclined to agree. As fantasy writers had done with Tolkien, 'cyberpunk' writers just skimmed the surface and missed the point. They just produced cheap knock-offs of Gibson's work, when they should have been finding their own voice.
The same is true of 99% of RPG setting design, I would say. Where it isn't simply stealing Tolkien's furniture, it's stealing Greyhawk's. People don't really create their own secondary worlds - they create Middle Earth with the serial numbers filed off, over and over again, all around the Western world, day after day, month after month, year after year.
MAR Barker was different. Der Spiegel called him The Forgotten Tolkien, but that was because (whether subconsciously or consciously) he is one of the few fantasists who has ever really understood what Tolkien was getting at: he created his own secondary world, and it was like nothing else that had come before or since. Like Tolkien, in Tekumel he created something genuine, from his own mind: his own consistent, living, breathing thing. He took the real message of Tolkien's legendarium and ran with it. In this, he was different to, and greater than, any other creator of imaginary worlds since Tolkien himself.
People like MAR Barker and JRR Tolkien are extremely rare. One is rightly viewed as a titan (although he is only just now beginning to be recognised as such by the literati), whereas the other is barely known, but it is hard to think of any other fantasy writers that come close in terms of their achievements of imagination. The death of MAR Barker is an extremely sad event and it can only be hoped that whatever small publicity that comes from it is enough to generate some level of elevated interest in his world.