How many games were you supposed to go before you ran into feeders and AFKers?
So by the same logic, if I go on a loss streak, then I get matched with people who play well consistently, win streaks exist and are meant to be. You think they just manufacture win/loss streaks to keep your win rate around 50%? Or could it just be the nature of statistics, combined with false correlations made subconsciously by your pattern recognizing brain?
You should try a little experiment... find a die, like a d6, d8, d10, doesn't matter... roll it 1000 times. Evens are wins, odds are losses. Now see how many times you win 5 games in a row, and then go on a "losing streak". I bet it happens a lot.