Entirely? No. But a huge part of design for published RPG material is world building, in one way or another.This isn't quite a contradiction. Publishing is something you do instead of playing at the tabletop - and game design isn't world building.
It's not so much that I disagree with you but that I'm not interested in blaming that individual GM for some kind of failure. I don't think that's helpful in any way. I have no interest in listening to the complaints of individual GMs either though. Sometimes, problems that stem from the group can be solved by finding a different group. Telling a GM that they're only stuck GMing because they've failed to manage their group properly doesn't seem to have a lot of juice in terms of anything we're discussing in this thread.Here I'd say responsibility isn't sole responsibility. The group, the game, and the current GM all have varying amounts of responsibility - and the responsibility any GM has shoots way up when they start complaining about a problem that they are the second best placed person to fix (behind only someone complaining but not stepping up).
I'd also say that a driver for the OSR is that Gygaxian D&D does a pretty good job (and far better than any subsequent D&D except 4e) of making GMing attractive
Gygaxian GMing is a subset of GMing, and a high-prep one. I think the amount of work it is almost certainly a barrier for a lot of people.

