I feel you. I solo climbed to Diamond 4 last season. Was placed into Plat 2 this season and failed 2 promos already. The game is fuckin easy, the issue is having 4 man premade who tag along their Low golds and give them any role. While they are there to have "fun", I personally want to win.
This season, there are so many new untested Ideas that are shoved into a small season for profit. The balance was always an issue but never to such extent. Now we have 140 Champions and 6 bans.
When I played in Tournaments, you could see most played champions on opponent's team and bans were truly strategic. However, in basic ranked rounds, you are unaware of most played champions and you cannot strategically ban. Now we have tank APs who dominate the game: Maokai, Malphite, Ekko, Naut, etc., because of how cheap and overloaded Tank items are. (2,700G vs 3400-3700G for AD)
I went from playing several times a day to once every several days. League has never been so disappointing. Riot's current priority is to cater the Bronze/Silver/Golds because they make up 91% of the League Community. Therefore, top 9% are suffering and quitting the game.
It is rather disappointing.