[ken]

Good point. It's probably a design focus of companies because it's named, and self-contained. You can put "Font" on a schedule, and a budget, and an A/B test. Your programmers can't really complain that it makes any other task more complex. It's the holy grail of design: some pixie dust you can sprinkle on at the end, which impacts nothing but makes everything prettier.

If, say, physics-engine-based layouts became popular for general user interfaces, it would take over the entire development of the product. It would affect every part of the budget and schedule and architecture. You couldn't feasibly A/B test it.