[Hammerite]

I think part of the issue comes with the fact that the people who made the older, more ambitious adventure games were just using what was available to make a narrative game (like people who made text adventures before them). Now that games have progressed, it's easier to create more open narratives that don't rely on the old adventure game tropes and so people who want to make more mature and ambitious games are able to work in different genres, while a lot of the people still making traditional graphic adventures (with some notable exceptions) are hindered by low budgets and somewhat dated storytelling techniques and gameplay mechanics.