Let me paraphrase Riot's responses to these questions and comments for the past 2 years for you, to save time. cough cough
Something something the system is working as designed something something hidden mmr something something we know we're not wrong because we have people that do math something something.
All in all, even though a large portion of the community has explained how our entire system is faulted and unfair, no one cares enough to make a change. Like, the fact that we're okay with "you get slotted against people with the same hidden MMR as you have, and not by ranking" should tell you all you have to know about the intention of this system. It's not about climbing or falling, it's about making people want to keep playing.