CHI research has become more complex (but not more insightful). The reason? Complexity is a competitive factor: it helps separate your paper from others. Lengthy papers with more substudies and details are more likely to do better than short but insightful work that might have more relevance for HCI theory and/or practice.
Reviewers are instructed to pay attention to HCI theory and practice, but in the case of short papers, they are afraid to take risks—they opt for complex studies that present laborious efforts, often with little truly worthwhile findings. There’s a Red Queen effect at play; authors are scared that their “simple” designs would get rejected, so they opt for adding more layers of complexity, more “stuff”, to impress the reviewers. And because the reviewers go for this, a lot of work that is simpler but would still be valuable, is lost.
Complexity has become a driver, a virtue, a goal in itself. Not good.