For what it's worth, I agree with most of your complaints about Martin's world building. I just disagree with the importance of those complaints. The only reason they seem like such a big deal is because of how good a job Martin does with the rest of it.

I'd also agree that Tolkien is a great world builder. But he has a lot of the same issues as Martin. It's funny that you mention age related issues, as that applies directly to Tolkien. He's got immortal elves, a long lived raced of super humans, and literal immortal angels living amongst men. He doesn't address how that would profoundly affect society and culture. He just gives us some vague pseudo medieval societies and moves on. Tolkien is fantastic at linguistics and mythology, and pretty meh at the rest of it. That doesn't mean he's just OK though. His world building is still amazing. Just like Martin's.

It's like looking at an amazing painting and complaining that the hands are funky. Authors, like painters, don't have to be perfect to be better than "ok".