Not a surprise given how many crazy changes the game has gone through. People get sicking of #adapting.
I played COH1 from very early on, I sort of remember one major patch that changed the game pre PE but that was only once, and it was nothing like the constant relearning you have to do with COH2 every patch. The game probably could have kept more people if it wasn't for that, every time I've come back it's always "wtf is going on now?" Hard to keep even casuals...
Quite the opposite really, the changes keep the game fresh for the people who play it the most (the pros)
When it comes to requests for help/advice given most of these issues have already been addressed dozens of times and people get burnt out writing the same response over and over again.