Unfair Matchmaking and Toxicity

1. I am lvl 24 and get matched vs plat/dia/gold. WTF
2. Why the hell... are people so toxic...?
3. How do I post printscreens that I saved to show what I mean? (prtnscrn taken from match history but also from lolnexus) the ryze was gold I think and was blaming botlane for the loss where we were winning lane in cs and kda? the fact that jinx gets fed later on in the game cuz they play as a team and our "Diamond" more like Boosted to diamond akali is suiciding all the time? Why is matchmaking first of all doing this and why the hell can't people point out their own mistakes blaming others?

note that i stayed ahaid of jinx in cs and been positive all game long as vayne vs jinx zyra. while pretty much every enemy was fed (which is why I wanna post print screens as well to show I'm not lying)