Why do people assume Solo Q lovers are bad teammates?

Every time someone loves to put in the fact "Well this is a team game, fk solo Q you guys suck at teamwork." The moron who can only work with select few people is a better teammate than someone who puts aside emotions and selfish desires to work with every stranger...? And yes you can be like "Why you so toxic referring to those people as morons." Well it's like going up to handicapped people who's missing limbs and going "Your life must suck huh?" Not that I'm comparing someone's misfortune to how kids view me on video games; it's just the lack of THINKING and restraint on some of these idiots are astounding.

Majority of premades I get in my team are horrid teammates. Maybe 1 out of 20 players in premades i come across might cooperate but most of them neglect the rest of us and report the rest of us for simply not being part of the group. I don't care about premades on the enemy team but SO MANY of my games have premades and most of them are the same crappy teammate who only work with each other and are trash teammates. Ironically they're the first to talk trash to us non-premades for being solo and shitty teammates.

And reports being less frequent... really? The game isn't any less toxic than it used to be. I don't have concrete proof to say it is more toxic either but it certainly is NOT better than what it used to be. There's an added frustration of dealing with toxic premades in my team in 80% of my games.