Why are new players put in such high elo games?

I don't know if this still happens or if they've fixed it, but when I started playing about a year and a half back I was a jhin main, at lvl 30 I went straight into ranked and I was put in a diamond/masters game and got destroyed. I was flamed by my team for being the reason we lost the game and I was, I told them I was new and it was my first game. I got responses like 'You're lying, you're boosted' or 'that's impossible'.

Eventually I was placed in silver 5 for that season so the games I had been placed in were obviously hugely off.

Does this still happen? It just popped up in my mind.