Pretty much sums up season 9. Snowbally additions to the game like turret plating and CS bounties (to shut down the 1 person on the losing team who won lane and snowball the winning team even harder), as well as the absolute debacle that was Positional matchmaking and the revert which screwed up MMR across all ELOs are both to blame to some extent.
But even in season 8, which was IMO not a great season, it felt like there were more close games and individual players had more agency to impact the game. Season 9 I feel incredibly lucky if one out of 10 of my games are evenly matched/feel close, AND I PRETTY MUCH ONLY PLAY RANKED as far as Summoners Rift goes, which is SUPPOSEDLY matching teams of "equal skill level."
Games in season 9 are extremely un-satisfying most of the time, winning in a stomp is boring b/c it hardly matters what you do b/c 2+ of the enemy were massively outskilled and fed your team, and losing a stomp feels even worse b/c even if you and possibly one other teammate are doing well the rest of the team are just way too heavy and unless you're playing way below your actual elo you won't be able to carry them.
I miss season 7, back then it felt like individual players had a lot more impact on the game and it was much less about the "matchmaking coinflip," Honestly It makes me wonder what the NA population numbers are looking like this year compared to 2017 and 2018, because even with the fresh lvl 30 accounts in high silver MMR and all that Matchmaking was providing much more evenly matched games and even though riot has made changes to make the game more snowbally and easier to end for the team thats ahead I just Cannot believe that alone is the issue.