Its probably not reducing queue times because most people are dodging if the get autofilled.
Its also hurting the people who are trying their best to give auto-fill a shot because they're playing the role they're autofilled to more often as other people run around dodging. As a result, they have less of an influence on a higher percent of their games when compared to all the people who are not cooperating by dodging (if you agree with the assumption that people who play their main roles will be more influential in a game than if they get autofilled, which I assume most people would agree with).
I also thing one of the big issues with the ADC role is the abundance of autofilled supports in games, so many games a single autofill actually strongly affects two people, not just one which is an even bigger imbalance.
EDIT: Please note, I'm not saying this because I disagree with autofill in principle. The idea at the surface makes sense. Its just in practice, as it sits now, its actually hurting the overall game experience especially for the good Samaritans trying to cooperate and introducing the opportunity for imbalance that you can't truly work into any algorithm, while not really changing queue times due to people dodging when they are autofilled.
