The demos haven't changed at all. The people making up the demos have. Apparently, there are no longer as many with "ballad-driven tastes" as one might expect.
If that is true, why is that? andrewduong77 wrote about how KMGL changed its playlist drastically since 2011, but I do not see how something like that could happen so drastically. It seems like in 2010, the "old" format was still intact, but 5 years later it is not? This puzzles me.....