I had a game recently where a premade 4 turned on me. First it was just 1 or 2 guys complaining about me, then I mentioned how the premade was probably raising the enemy mmr, making it harder for us to win in general. They took offense to this and all starting getting on my case, I proceeded to mute them with no further response.
At the post-game lobby one of them tried to get the enemy team to report me for "trash talking". They (the premade) in fact were the only ones who ever did any trash talking, I just stuck to what I believed to be facts, and said very little all game (probably 2-3 sentences in response to their whining). We won that game, and I'd say I had a pretty hefty hand in that win, but I guess their ego was a little bruised by me stating unbiased information for 2 seconds, that was only meant to explain why we might not be doing so well (assuming the enemy team didn't also have a 4-man premade, which didn't seem to be the case if we're going by tags, though that doesn't definitively mean they weren't a premade).
Oh well, I am fully aware that situations like this will never hurt me or my account, it's still kind of annoying in the moment though. I wouldn't be surprised if groups like that end up getting group suspended. They weren't nearly as bad as many other groups I'm sure, but that might only be because I gave them so very little to work with by saying almost nothing.
It would indeed be nice to have a pure solo queue, that did not even sometimes include a duo.