Champ select idea to decrease toxicity

So when you enter normal champ select, it brings you to a screen where you can click to choose a role, when a role is taken, the tab grey's out and becomes unable to be clicked, it then brings you to champ select lobby.

I know that this won't stop trolls from saying "mid or feed" or stops them from instalocking, however it will prevent a lot of arguments based on who called first, people who join late and don't see the previous calls ,and it will also stop premades from fucking someone over.