Why is it if i report someone , im paired with them again via ranked flex?

Long story short; I played a match with my friend 5v5 flex and got a trio que who flamed and fed. Started a que up again two minutes later(to prevent running into the people we just finished reporting and avoiding) it puts us in the same lobby with the same 3 people who just finished flaming and feeding. My question is if you report someone do they not get blacklisted like in many other games like Overwatch ?Id just rather not deal with such an experience again.