Silly question about DynamicQ

Why did Riot force Dynamic Queue into ranked?

Why not make DQ only in normals?

It's like perfect place for casuals playing together in prearranged teams..

PROS:

• ranked matters again
• skill matters again
• no more unfair advantages cause skype
• no more legal boosting
• prearranged teams can still enjoy killing solo players

CONS:

• all the shit we have with DQ atm would be thrown onto casual players
• skill disparency would skyrocket to extremes... Untill matchmaker would sort things out (give or take 3 years and few matchmaker updates)
• solo players are still slaves to prearranged teams (which will not change for as long as DQ exists)
• "normal players" would be unhappy, obviously, but in the end Riot made DQ with casuals in mind...