It's a great question Av, and something I've been considering for a long time. I think it boils down to a whole combination of things like you wrote - so here's my ranked list

- The game is really inconsistent, as in the bad parts are really bad but the good parts are actually really good. This basically means it polarizes opinions. Example: I've never had an issue with performance, but can empathize with those that do, but at the end of the day it's not a problem I see. When I do get bad performance I rage.
- MG are really really slow at fixing things, so while any community has 'haters and fanboys' most of the normal people are getting bored and have lost interest now. As nature abhors a vacuum, that just leaves the obsessives or trolls to party as middle-ground people usually want no part of the conversations they see here.
- 1C is to healthy community communication as Josef Mengele's was to the art of paediatrics. They haven't got a clue, and generally do the exact wrong thing. It provides new angles at which to wack the dead horse every couple of weeks or so. Keeps the stew simmering.
- People hate change. Some people got IL2 working just right on Windows XP and always saw CloD as a threat, i.e. the shiny arrogant usurper. Lots of bloated promises from foreign sounding people that should get their's in the end etc.
- It uses Steam. Some people hate Steam, and we just have to wait for them to die; which given the demographic and their blood pressure won't be long.. lol
- Flight Sim fans often have fan-bases like sports teams from the UK 1980's. They basically come here just for the fights or to watch fights, and if any talk about flight sims happens then that's more by accident rather than design. We used to get IL2 fans on the RoF turf until it flares up and then collapsed under it's own exhaustion, we sometimes get IL2 fans torturing the Gaijin forums - but this CloD Extended Forum is special as it's a legitimate place to just come to rant / argue / troll even if you've not had time to see the game yet. It's the only unique place in SimHQ set up just to troll people (bar PWEC I guess), and it provides a lot of entertainment for those into that. Given that product forums like 1C, RoF and DCS on their own site moderate more strongly than here (i.e. keep making the same complaint again and again), then we get left with the outcasts who get some small satisfaction out of a mutual circle-jerk of baiting. Once the last positive voice, or anyone wanted to be reasonable about having a discussion, has left the building then they can claim victory and then move on like locusts to some other place where the circle will just get repeated. It takes two to troll, and due to the polarization the game brings means there's been rich pickings in this little corner of the net.
- The flight model over 18,000ft is not accurate for Oct80 fuel in 1940.