Over time, more players queuing up at a time should make games even more balanced than they were before, once elo gets sorted out properly. More players to choose from should mean that the matchmaking system works better, so I think the increase in player count is for the best. Also, as others have said, if you want a level of play that's a little higher, come play mixchamp or pugchamp.
Also, I think that people should remember that all these new players are the future of comp TF2. Every time you're toxic to someone who simply doesn't know how to play 6s properly yet, you're actually hurting the chances of survival for the community as a whole by limiting the chances that that player will continue to play and actually get good at the game.
We were all absolutely garbage at 6s at one point. I believe that the more you help new players through constructive criticism, the more likely they are to improve and stick with the game, sustaining the community as a whole.
Here, lemme get down off my soapbox.