What happened during this reset?

So far, it has been a terrible start to the season. I went from high silver last round to middle bronze after going 7-3 for placements. I thought, okay, i can carry through this, but I've promo'd twice and have had trolls and afkers constantly. I usually win lane and rarely die in lane, but then the fed guys everywhere else come my way from the map and it's GG. You would think these baddies would be weeded out, but since it looks like reporting does nothing; they're still here to stay. I was actually enjoying high silver because the super toxic people weren't that prevalent, but now that I've been thrown into bronze, this game feels unplayable, and is far from enjoyable. The toxicity is amazing, and the grind feels impossible. I've seen others with the same problem, too. Plat friends last season were put into bronze 2-4 after positive placements, as well. What is going on? It feels like the whole ranking system is majorly broken.