Unfair Mathcmaking

Hi Riot. Today i played a game whit one of my Bronze 5 friends. He is not that good at the game, but i like to play whit him cause he never flames. Well, when we went into the game, My friend, there always checks our matches on LSI, says "They have 2 plats and a DIamond on there team..." ¨ I first didnt believe it, cause we were B4, B5, B3, S5 and S3. It turns out that there Lucian is diamond and mains adc... I dont think its fair that matchmaking is like that. The 2 silvers on there team were feeding, but still won cause of the Diamond and Plats. The Diamonds and Plats were very toxic, and flamed us for not being good enough. They said Things like "Pls... i fall asleep here. Can yuo at least try to win a trade whit me..." I dont think its fair that a team whit low elo can get stomped that hard, just because they were all pres... I think the matchmaking should be better.