The top players in anywhere but playing vs Masters and GMs are winnin 70-85% of their games though pretty easy.
Average player who is still improving for example in silver-diamond will see the 55% winrate but a GM in Silver would be doing the 70-85%.
Right so this is another matter where low skilled players try to justifity for themselves why they are stuck at low ranks.
Funny that they literally search every other reason of why they cant climb up than face the truth that they just need to get better. Sooner people accept that fact they can focus on learning to play better and climbing up would happen as a sideproduct
i am starting to think this forced 50% win rate in quick match is VERY real a few days ago i had 5 win row with Lucio, and then lost one game and then won two more with sylvannas and Raynor, and today i am on my 6th loss and have now felt so depressed that i quit my latest 2 games due to being twice thrown into a game where not only was i matched with a terrible team combo, twice in a row a player disconnected from the game right from the start. So it does seem that when Blizzard sees you performing well, you are thrown into a match with people who needs aid.
Necro threading is not very appriciated on forums, just so you are aware.
Anyways to answer your question, Blizzard even answered several of threads like this them selfs on the US forums.
Explaining as to why it seems like there is a 50% forced winrate.
Would be silly if you think people could actually FORCE it in any ways like that.
You are btw aware that you do have a rating called MMR even in QMs right?
That in it self should explain it all.