I hopped on a bronze smurf to test boards theories
I didn't experience anything like what boards users complain about. Games felt well matched. I was up against other smurfs in just a few games. Nobody was extraordinarily toxic. Games were fun and regularly lasted 25-30+ minutes, so there was plenty of time for even late game scalers to carry. I saw a variety of champions, lots of crappy yasuos but it's not like people were picking only the op stuff. I got 30+ lp per win and -5 per loss, I couldn't stay bronze unless I tried to.
So why do boards players complain so much? The game feels fine to me.