Matchmaking isn't the best. That being said, when I solo queue, it seems like the solos have given up before the game has begun. No one pushes to the objectives. They don't hold them once they have them. They make people try to capture alone, instead of joining them. Which would shorten the time anyone is stuck on the point. They don't force power plays. It's like people don't even want to compete.
Yep, I usually 3 stack with two buddies I grew up with, and we regularly see the solos we get do next to nothing to win the game. They hide in the spawn, stay on home flag, capture C putting us in a spawn trap on some maps, and never push with us to try and win. I have no issue with solos, unless they play like this. In that case, I'd rather 3 v 6 with my buddies.