Except matchmaking algorithm is based on EOMM, behavioral score, and MMR.
It's not like flipping a coin.
Matchmaking knows within a 95% confidence interval which team is going to win and which team is going to lose.
When matchmaking makes a team with 2 duo pairs, 3-4 divisions higher, and all 60%+ w/r, and are all on 3+ game win streaks, while your team has no duo pairs, has players 2-3 divisions lower, and all are sub 45% w/r, and are all on 2+ game loss streaks, then the matchmaking system intentionally put you on the disadvantaged team.
If your match making is like this 8 games in a row, you are in loser's queue. It's not a coin flip. It's intentional.
https://www.youtube.com/watch?v=KIfaZtt6nV0