Because reporters have to write stories and a GM's or coach's quotes add instant credibility to your story, no matter how disingenuous the answer may be in reality.
I'm sure most reporters will tell you that GMs and coaches alike answer questions with some kernels of truth in them, however they also try not to let themselves answer a question in a way that undermines their team or gives away any competitive advantage. Even while participating in pressers, coaches never stop coaching and GMs never stop GM'ing.
SSh! You're going to ruin the ongoing "Buddy was terrible, Doug's a genius!" narrative.