Why is there so much toxicity above 17+ Voobly in TG's?

So I've been around the block a long time, played on the Zone, then IGZones, HD, and finally Voobly. Over the course of those years I've improved a lot as a player, finally settling in around 1650-1750 range on Voobly MS, which I doubt I'll improve much further from. My experience so far had been that as I improved, the quality of the games and the players increased - people were more helpful, more cohesive, better at achieving team synergy, but since breaching into the 17+ games, that trend seems to have reversed.

I'd never claim to be a pro player, but I know some tricks. I do know my weaknesses - I'm not very fast (an old injury limits the dexterity of my mouse hand), which means during high-multitasking scenarios, it can take a second or two sometimes to respond if I'm engaged somewhere else.

Once I reached 17+ level, people become relentlessly intolerant of any small mistake - maybe that's fair enough, this is the "big leagues" after all, but it's excessive. People will start flaring 20-30 times a second, and continue doing so even after the indicated action has been taken. I don't know about anyone else, but this is extremely distracting and really hampers my game. They'll flame for the smallest things - I was pushing some deer for a 19+ guy the other day, and one went back while I had to jump back to base to quickwall against a drush. He paused the game to chastize me for it, and continued flaming me as a "noob", even after I'd dealt with the drush and came with knights without any delay to help him. He'd simply decided I was a worthless ally, and spent most of the rest of the game micromanaging and nitpicking my game in really un-useful and distracting ways. We won that game, and I wound up with the MVP badge, but for this guy it just wasn't good enough, because I missed a deer lure for him in the early game.

And it definitely isn't just me. Yesterday I specced a game in which a 2K guy was unhappy with the units his pocket sent in imp (he wanted gunpowder and the guy went paladins, although he hadn't said so). He sent villagers into his ally's base and walled off all his stone and gold, and then went AFK until the game ended. Then you look among the regulars, the guys steadily in the 18-19+ category. Many truly seem to hate each other. I've seen many lobbies fail to start a game, because 3 different guys refuse to team with each other, and a split couldn't be worked out.

I don't know if it's done behind the scenes or what, but the real pro guys don't seem to act this way, but sub-2.1K, I feel like it's a major impediment to playing at that level if your allies are sitting on your shoulder the whole time, telling you how shit you are. I never felt like I gave less than my best, nor have I ever given up or folded without doing whatever I could to advance my team.

Why does this happen to people? At that level they're in the top percentiles of all AOE2 players, they probably play several games a day. All this anger and bitterness can't be healthy if they're losing their shit 3 times a night raging at people. Why call anyone a noob at all? Everybody in that weight class has earned their right to be there, one way or another. It just seems petty and childish to split hairs at that point, especially over tiny things.