Riot fixed it already, just tested it on 13.22 live server.
Can confirm game is not starting after champselect on live servers with patch 13.22, I just get the option to reconnect in the client, but still unable to start the game. Client works fine, usually it's the other way round. It seems they are aware of a problem causing games to crash, as stated in the notifications in the client.
in short: ingame: flawless , client: decent, but not perfect
I've been very actively playing on linux for over 3-4 years on opensuse tw and nvidia drivers with lutris installation. I had no issues ingame that were linux only, aside from recently seeing the taskbar at the start of a game sometimes and having to switch to fullscreen and back to borderless, after lutris-lol-ge update some weeks ago. And I remember at the day of first installation years ago some input loss, caused by some missconfigurated stuff which I could fix, but nowadays it installs and runs without any noticable flaws ingame.
The client nowadays works decent but not perfect, slight delays on UI button inputs (noticable in champselect, take an extra second to make sure before locking in), dodging games is pretty much a gamble it only works sometimes (closing every process doesn't help), hextech crafting is slow/delayed. After a game, the client sometimes hangs just like on windows and needs a restart.
The problem with switching champs and locking in first occured to me 2 maybe 3 months ago, never before. So I'm not sure if it is the same as the reddit post comment.
Not getting the correct rune page is very inconsistent for me, I know it happens sometimes to me for a long time, but I can not reproduce it when I try.
Hextech crafting is very slow/delayed for me, but Loot tab is a mess in general even on windows.
Problem persists for me with lutris wine-ge-lol-8-27-x86_64, only sometimes it's smooth und fluently.