efficiency and creativity don't go together.
First, while it is true that good work takes time, I'm not sure that sort of situation actually apply to Kojima who apparently had all the time, budget and indulgence he needed.
Second, looking for ways to be efficient while imposed with many limitations needs creativity to begin with.
He's not entirely wrong, I mean yeah a lot of artists are efficient if they're just working for a paycheck or something they don't believe in but If it's a passion project or something they own they're going to keep working on it until someone tells them to stop. I'd argue that the biggest challenge most artists face is learning when to stop polishing.
One could say that if you gave an artist unlimited time to finish their work, then it would never be finished because it would never be polished enough in their eyes.
So a creator who actually has self control and knows when to stop by themselves is a rarity. It's an generally good and important trait to have. I really, really hate this insinuation that efficiency automatically means non-creative or paycheck-to-paycheck work as if they are diametrically opposite.
To be honest, some of the praise I read for Kojima in this thread regarding this perfectionism grates me somewhat. Things like "he doesn't want to compromise on the resolution of foliage" as if any creator wouldn't want their game to look as good as possible or "he re-recorded VA lines in the last minutes" as if any self-respecting director wouldn't want to do that if they could.