Matched Against Plats as Level 10 New Player?

I just watched my friend who is new to LoL play his first 5 matches of pvp after he did 10 or so in bots. I did not queue with him, I just watched him and gave a little bit of advice. He wasn't actually doing badly, but then the enemy jungler who is Platinum just wrecked everyone on their entire team. This was a team of level 10-20s vs a team of level 30s , silver 1, and plat 3. The enemy jungler ended the game with like 20/0/5, and all the new players accused him of hacking, but it's no surprise a player with 1000s of wins would own these brand new players.

Next game, the enemy adc/supp are two golds. Everyone else in the game is level 30 or lower unranked. The gold duo wrecked the game and after getting 8 kills in the first 5 min, 2 people on my friend's team AFK'ed.

This happened again in the next 2 games where my friends' team would feed hard before they could even make a difference in the game. And not feed intentionally, but because they were matched against golds/plat.

Then the 5th game he finally gets the plat on his team who carried the game pretty much alone. Why is the matchmaking so terrible at low level? The golds/plat he was against weren't even smurfs.. so why are they getting matched against level 10 brand new players

This is a terrible experience to give a new player to this game, the first 5 pvp games he got to play were a joke, and I wouldn't be surprised if that ruined the enthusiasm he had for this game before.