Is it just me or RIOT made it near impossible to get S/S+ and when you do get it, its random af ?

I mean look at my last game, I absolutely killed it as Zilean. Least deaths by far, good kill participation, by far the most wards placed and destroyed, hell I even racked up some farm and did more damage than half the enemy team and in general I solo carried that with my stuns and ults. And poooof again for the 100. time I get S- . But then comes the random game when we stomp at 20 minutes and I get S+ with score 4 0 4 ... Obtaining the mastery level 7 this season is honestly a fucking chore, especially on mages, supports and ADCs because every single champion can 1 shot you at any given moment and it looks like with more than 2 deaths you automatically get denied the token you deserved. Few days ago I had a monster Akali who solo carried 1v5 with 40+ kills, but god forbid she dies, she had like 5-6 deaths and she didn't even get an S- for Christ stake. Is there anything else that can get destroyed by RITO lately, meta - destroyed, balancing - destroyed, champ design - destroyed, matchmaking - destroyed, client performance - destroyed, hextech crafting - destroyed. Literally the only single thing still functioning are the art team and hats of to them.