About The Soft Reset

I was Silver 3 last season. After the soft reset I played my 10 placement matches and won 5 out of 10. I ended up getting placed in Bronze 3. I did decent in all my games and even lost games where I had a dream team just they had more counters to our team comp than we did theirs. I thought I would at least place Silver 5. I really don't feel like grinding out of Bronze again. I'm pretty sad about it, and I'm not alone. I played a few games after placing and EVERYONE was mid silver last season. Can anyone explain this?

P.S.- Also when I first started playing ranked, I was put in Bronze 3(Season 3). Maybe this has something to do with it? I hope this doesn't repeat next reset as well, if so I think I will just stop playing ranked.