A "competitive mode" isn't really required. All you are really asking for is for matchmaking to only create games where both teams are close in rank (as it should be). Currently that is not the system and Aljo has alluded to that being because the wait times would increase even more if they walled off by rank. I agree on the frustration factor as while I haven't seen the behavior you displayed in your vids, my team frequently matches up against teams 5000 RP off of us in either direction.
I do have to wonder what this indicates about the size of the player base that matchmaking can't support stricter rank (or team size) filtering. Its pretty fundamental to online gaming and something that's been part of the series previously.
