>By publicly resigning and publishing why, he's literally confronting them in the most effective way possible.

It wasn't public though. From the post: "I chose to leave quietly in February 2014, and not publicly state why I left."

He didn't say anything until now. If he was confronting it don't you think he should have done so in 2014 instead of almost 5 years later and after Cecilia D’Anastasio’s Kotaku article? This seems more like a means to distance himself from ever working at Riot.

The article states explicitly that he did not publicly resign and only released his story years after. He even tried to go back.

Not really effective- it's the most confrontational way, and the most divisive, but I doubt it will really change anyone's minds. Instead you'll get zealots from both sides of the issue yelling down any reasonably conciliatory approach as they use it to further their own agendas.