My experience with Overwatch ranked was brief, and awful.
It was a while ago, probably 3 months or so.
I joined a game. 2 people on my team left. Guess they disconnected or whatever.
The remaining 3 players of my team left.
It was 1 vs 6.
I stayed for 1 round, fought them for a bit, messed around, but they weren't especially friendly or fun to play against in a 1 vs 6 (they weren't willing to give me a chance, just wanted to spawn trap me etc).
So I left.
After leaving, the game told me I had been punished for leaving a game, and would earn a fraction of the rewards for the next 10 games.
I don't know if this has been fixed now, but it was singlehandedly the worst treatment I have ever felt I have experienced at the hand of a games developer. I was the one that stayed till there till none of my team mates were left, and I received what I considered to be, severe punishment for doing so.
That was the last time I played the game since this uprising co-op thing recently. Which seems alright, but I don't trust Blizzard to manage a ranked system.