Or maybe, just maybe, these guys made great games because they were surrounded by great people. That QA guy who gave key insights into how tedious certain game mechanics were; the "bad executive" they all hated who reined in their unreachable goals; that one developer who applied his good game design senses despite not being a designated designer.
I find the notion of auteur "game developers" somewhat puzzling. I say that as someone who played, and still play, these games when they came out. Most of these guys haven't made great games in a long, long while. Obsidian's only decent game in a long while is Pentiment, and that for all intents was a passion project.