I've seen this so many times
I was part of the original space exploration discussion forum on Usenet when the Internet was still called the "Arpanet". Many of the discussions that we're having today (Moon vs. Mars), I was having with Henry Spencer, et al, almost 18 years ago. I watched that early forum slowly decay away as the loons took over. Since abandoing Usenet, I've seen this happen again and again. The rule for open forums on the Internet is simple: Loons accumulate, rational people leave.
Gary