I'm using the basic dictionary definition of "decent", are you really struggling with that?
- conforming with generally accepted standards of respectable or moral behavior
- of an acceptable standard; satisfactory
By the definition of the word "decent" most people are "decent".
"too many bad days" is likely mathematically defined by being a certain percentage outside the standard deviation, which would in turn be defined by the majority of decent players and how they act/report.
Riot doesn't need to teach "billions" because billions aren't being banned.
The game's got 100 million players that play each month. If you assume that 50% of these players are banned and need to be taught, then it'd take over 3 years for there to be 2 billion (the minimum for "billions") players to accumulate to be taught. If you're going with a more realistic number of people banned of 10% then it would take over 16 years for there to be billions of players to be taught.
You're also acting like the current ban system isn't educating the banned. You get a punishment letting you know your behavior wasn't OK, you get your chat logs, you can see what you did wrong, and if you've got doubts on what was wrong you can post on the boards and they'll help you find out.
Even if you willfully ignore all that, creating a video on basic game manners would take less time and effort than creating the filter.
Notice the bold part? That includes the toxic people. Why should they get banned and you don't?
Toxic people ruin the game for a significant portion of the player base. At minimum, they ruin it for their 4 teammates, but they can also ruin it for all 9 other players in the game.
A toxic player is very much like an opponent in Chess that cheats, moving pieces where they don't belong. It's irritating, you're no longer even focused on the game you set out to play, and no matter if you beat them or not they've made a mess of the match and you're left wanting a real game.
What makes a player "toxic" is on them. They have full control over their keyboard, they can chose what they type and they can chose to hit ESC instead of ENTER.
I, for one, don't think anyone is so far gone as a human being that they can't behave decently. It's even easier to be decent in an online text-based setting than it is in the real world, since you can edit or retract statements before they get to the other person.
I believe in you. You can do it.