The more I think about it, smurf accounts seem like the root of all evil.

Client bugs, in-game bugs, and Vanguard errors are just the default. Next, a few of the currently cited reasons for people leaving LoL:

1. Smurfs
2. Account sharing
3. Boosting

Things like this, and they're all able to run rampant because creating smurf accounts (multiple accounts) is possible.

Since you have multiple lives, some users exploit it badly, and Riot is the one providing the opportunity for that.

Of course, it's already spilled milk that can't be picked up (it's hard to target users with smurf accounts now). Riot's position is that they 'will try to crack down harder.'

But since the visible effects are small, they can't prevent players from unknowingly getting wrecked by ecosystem disruptors (smurf or booster accounts) at least up to Emerald, then hitting a wall and quitting the game. Even if they make newbie-friendly patches, those new players will eventually experience the same thing when they start ranking, so it seems like nothing is actually being solved.

This patch that's looking out for newbies is ultimately just a show to suppress the topic, saying 'We've recognized the issues and are trying to solve them' – Riot probably knows it's almost ineffective method-wise.

At this point, Riot must have a headache too. If they just blocked smurf accounts, dozens of problems related to player attrition would be solved, but actually blocking them would cause unpredictable backlash, so they probably think the current loss is still better and aren't directly touching it.