He thinks he's as profound as JRR Tolkien
Well, he's not, NOT BY FAR!! For one thing, he hasn't set out such lofty goals as a "mythology for his country", he's just been besotted with foul language, gore, sex and violence in a way that JRRT never was, and he's doing it to appeal to the lowest common denominator of peasant in the world.
Another problem with Martin is that he's never actually finished this story, if it is his magnum opus, but he's been distracted for many years about it. He allowed hack writers like Dumb and Dumber (I don't care what they're actually called) to absolutely ruin the TV show based on his magnum opus, Game of Thrones, because he couldn't be bloody bothered to finish the books beforehand. And to be honest, the TV producers of that show were stupid for allowing it to be started before the STORY WAS FUCKING FINISHED!!! Tolkien's magnum opus, LOTR, was finished DECADES before any adaptation!
And above all, JRRT never wore a stupid hat or glasses, but he did smoke a cool pipe. This is why TOLKIEN WINS, EVERY TIME!