How hard is it for people who work at riot to fix matchmaking?

So I recently had a game. With a level 30. In my silver 2 - gold 3 game. I checked his previous matches. I saw 3/13. I was thinking, oh, maybe it was just a bad game he had! Apparently he is that bad. He went 0-17. They just blame their teammates. I played bad that game. But I tried. He cried like a baby about how I didn't gank when he went in while I was farming on the other side of the map. How is this matchmaking? When I started playing league. I had to play from the lowest of the low. Bronze 5. I wasn't good back then. But looking then and now. The game had better matchmaking. Now if you just get unlucky your team has to be with the level 30 freshie playing ranked with silvers-gold. I despise this so much. There are so many people who have to deal with these trolls. I cannot see a future with this game even being known if Riot is just giving away free ranks to bad players. Please fix this matchmaking in Season 10 or very soon.