BYU's struggles this year have been because it has not guarded the perimeter consistently regardless of where it plays.
I've heard Mark Few criticize the WCC's commitment to basketball. If the 19th ranked program in the country can barely fill a high school gym while playing BYU then I don't see the other teams being in a position to make major investments in their basketball programs.
If teams who play in high school gyms get extra motivation when their opponents note that they play in high school gyms then that's great for them. I'd love to see the data. I expect Dave Rose is much more concerned about his team's defensive mindset than their Instagram posts.