If arty is "paper" hence a necessary game mechanics element, what is the World of warplanes equivalent of arty? Is every battle without arty a game mechanics fail? If arty is equal to all the other branches, why are there no 15 vs. 15 SPG battles? If WOW doesn't include AA guns, it can be considered an admission by wargaming that they didn't think WOT through.
I guess people (including me) don't like being shot at by something you can't can't shoot back at. I can't see tanks/TD's shooting some of the time but I can shoot back at them all the time, yet arty is out of reach. And once you beat the odds and actually reach them, they still stand a good chance in a 1 on 1 battle.
For the record, I do hate arty. For over a 1000 days, they kept my Sarajevo under siege, shooting exclusively at civilian targets like houses, hospitals, mosques, churches, synagogues and any locations they thought were occupied by people, killing and injuring over 100000 civilians. That is until the US forces showed up, then they ran like little bitches and the in game behavior of arty is just as cowardly.