@ThefortySN or any one else who wants to chime in.
Why do you feel a simpler alternative, that there's just bad players on league and you will find them on your team sometimes is not the case?
Why the hell do folks feel its more realistic riot is trying to rig matches or add extra handicaps to folks climbing?
Also why do folks think 3 is even remotely large enough as a number to be considered a streak?
Why do folks think they will be protected from having shitty teammates?
Look Elo systems even with modifications for team play require a high number of games, 100s of them, to accurately place folks close to their true skill and their assigned mmr. When your dealing with 100s of games a "forced" 50% becomes the time your least likely to see a long streak Take a look at how often you can see strings of 2-4 flips even in a small 100 sample
Now if your good, if your winning more then you lose, if your win % is higher then 50%, get this, your actually more likely to see a win streak. WHOAH! MIND BLOWING. Now again if we set 3 as the minimum for a streak, which is already common as hell even at 50% your going to see streaks all over the place for wins. Yet any loss becomes a rigged game, if you happened to have a bad teammate.
Your setting up this scenario where any game loss after 3 wins because of a bad teammate is matchmaker wanting to punish you! an yall do this in a way that ensures its 100% true when your complaining about it by completely ignoring anything else. No ones sayin "OMG I had 5 wins then a really close game that we lost, RITO RIGGED DIS." No ones, "man I had a 20 game hot streak then I got super cocky and fucked up bad and single handedly lost the game for my team, MATCHMAKERS GARBAGE!" Its any time you lose a game after what ever you consider a streak = WTF matchmaker hating on me, because you only look for lost games with a bad teammate after a "streak" (again, to drive this home, 3 games is a grossly low number to use. Back in my day a streak meant I filled My entire match history with wins then screen capped it and posted it on to best friends FB wall with a friendly jab of GET TO MY LEVEL BRAH!)
And again, unless your at 100% win rate you will see either a more dramatic (high % = longer string of games) win streak or more frequent (over 50% resulting in more often to see strings of wins) break into a loss.