I am going to get downvoted to hell for this

sure maybe it doesnt improve your individual skills on how to play the game , maybe the queues are longer . but atleast it offers a healthy and a fair match , means no trolls or toxic players , when you play with 4 of your freinds you actually trust them you don't flame each other you help your lane losing partner and share advices between each other, you have synergy between each other as you communicate in ts you
this almost never happens in solo queue in solo queue for example you go jung you get a lb mid which dives cho gath at lvl 3 and then he flames u and then he goes afk giving ennemy free boost , then the lb shares the tilt between the team , here you go you lose because of a damn lb who sucks at making decisions and ragequits .

I am sure riot is aware of that , and they gave us this because in the past we ranted about trolls and ragequitters

EDIT : i know there are those who play solo will downvote me to hell , but don't get me wrong , i used to be a pure solo queue player , there is nothing i hate more than having a toxic player in my team that gives free boost to ennemy with his negative attitude , idc if he gets punished after i lose Lp because of him ,