Comment by dwaltrip

I would guess that the increased rate of information transmission across society has contributed to this trend. Copying is a key mechanism in how culture develops and propagates, and information moving more easily makes it easier for different groups to copy the dominant examples for any particular activity or discipline. A lot of information systems and cultural phenomenons have winner-take-all / power-law dynamics. Combined with increased information transmission, this would cause the leading styles and practices to become even more dominant.