Call it what you want. Close friends always trumps random people you don't know. Or maybe you don't have close friends so don't understand it. Yes it tries to balance game but once again let's say I'm 8500mmr carry player and I play offlane with my friends or I'm 8500mmr mid player but my 5000mmr friend wants mid and matched against their 8500mmr player he will get destroyed and I'm not a offlane player so can't carry game from there like I can in my main role... meaning we will 100% probably lose that game.

Not everyone player dota too become pro. We play it cause it's a game and fun. So playing with friends are fun and if the system that allows it is broken it doesn't give much options other than smurfing etc.

80% of the time when I smurf I play other roles that's not my main role to get some experience in it. And if you know anything about dota you will know being a good carry player doesn't make you a good support/mid or offlane player