Hand eye coordination test and internet lag test before playing normally
People usually points out the problem with bronze is that we have no map awareness and decision and warding and stuff. But about 30 % of bronze are "super extra special group of people"
they are neither trolls or very eager to go off meta. They are just trashes of the league, playing with bad internet and just bad at pressing keyboard and mouses in general. I have personal experience with this.
Bad internet
When i was 12, I started playing league of legends and realised how much of a team game this is. My internet was bad and was constantly having 200 ms or above, i would constantly feed the enemy. I forced my self to stop playing league for 2 YEARS UNTIL WE MOVED TO ANOTHER HOUSE( lots of determination). Because i feel responsible for loses and will take full responsibility. But not all players are like this, they continue to play and ignore everything.
My suggestion is that integrate a periodic internet check when the account is created. There will be a standard and if an account fails the standard for example 5 times in a roll, you will be banned from league until you request another check and pass.
Bad hand eye coordination
My sister is a great example of this, she is 14 currently and downloaded league 2 month back. I started playing with her until i realised how bad she is. We went in to a custom game and it turns out she couldn't even recognise left and right mouse button properly. The next day i was watching her play and i got so tilted for her team i dragged her of the game and uninstalled the game on the spot. She sometimes re download the game behind my back but i uninstall it right away every time i find out (she is still bad and haven't improved) I told her to practise her key pressing on pc piano tiles and practise her mouse skills on aim booster. But seriously these kind of people shouldn't be playing League.
My suggestion is that perform a hand eye coordination test on very new user. For example click all the dots on the screen or press the key shown on the screen with a time limit. People who fail the test will be banned from league until you request another check and pass.
I know there is a lot of flaws in those test for example other people can help you cheat, or perform the internet test on another computer. But i am really sick and tired of those players ruining my bronze game (my diamond 2 smurf friend helped me from 42 lp bronze 5 then after 4 games neither me or him can carry and i dropped to 0 lp)