DQ is just RIOT catering to casuals
There are too many variables for DQ to successfully evaluate skill. For example: skilled friends, voice communication, skilled players on the other team to compensate, etc. This makes ranked ladder untrustworthy. Whatever RIOT will do they won't be able to balance all the variables for a true competitive ladder. People will see this and in time, the heaviness of being a high elo player in season 6+ won't mean anything anymore.
With time, LoL image as a competitive game will change. Casuals don't care about DQ, they just want to play with friends and have fun over skype. And yes i know, they make up most of the players.
Now is this a good decision? Destroying ranked ladder while catering to casuals and calling yourself a competitive game? We will see. Labels are strong. If people stop believing in the heaviness and competitiveness of your ladder, none will call it a competitive game anymore.