Well your bitterness towards them seems somewhat understandable from your point of view but I do not feel it is deserved...or at least not from what you've told me so far.
Several forums that people I know have been on have dried up as a result of Ponies invading. This forum is slowly in that process. Many members left for MLP forums and haven't looked back. As such, I'm allowed to bitter to ponies
First off your statement seems to be contradicting itself in a way. You said forums have dried up from "Ponies invading" and then you say these forums are in the process because many members left for the mlpforums.
If they are leaving how are they invading?
I'm not sure what other forums you are referring to but regarding the Wii U forums you must remember that these forums are centered around one video game console, one that is rather unimpressive directly compared to competitors. There is only so much you can get out of forums like that, yes there is a lot of other Nintendo talk and what not but it's not a place that will live as long as the mlpforums.
You should not feel bitterness towards ponies simply because members left to join the pony community. It's their choice and if they are seriously all leaving for that place maybe it's because it's a better place. If they find it better there then why should they force themselves to stay?
There is a huge difference between the Wii U Forums and the MLPForums.
The difference is that over in the MLP community we are people (ponies) brought together by a common interest in a creative, joyful and loving cartoon, but it becomes something much more as this common interest grows into long lasting friendships and people from all over the world coming together to share and teach and learn and for the most part spread love.
Over here on the Wii U Forums it is simply a common interest in an arguably gimmicky console and/or video game developer. Not much can grow off of that, sure you can discuss things all day long and share opinions but video game consoles are not the greatest seeds for growing connections.
Now Nintendo and the Wii U are not the point of this post. Surely you have a right to blame ponies for the decrease in activity and stuff like that because it is actually their fault, I accept full blame that the community I am in brings people from other communities.
I think it's best compared to a government blaming another country because their citizens have left them for that country. They have the right to blame the other country for being better but in the end the logic is actually quite selfish.