The Flex Queue "Fix"

I'm interested...what exactly did this fix?

From what I've seen so far, the biggest thing that's changed is people's ranks going down. I personally went from Silver 4, to Silver 5 but I've seen people go from being ranked at high Silver to Bronze after this change...even if there's time to climb, that's extremely annoying to deal with if you ranked so much higher the first time.

I won most of my 10 starting games and I won the last deciding game after this fix, why did I go down in rank?

Idk at this point the new flex system just feels so messed up