I don't know if this is a troll thread or a serious claim. Assuming it's the latter, Ezreal is not cancerous and he's certainly not easy to play. He's a safe pick because he can play much more passively in lane than other carries while stacking up for his mid-late game spike.
Saying Ezreal is "serves as a staple champion for those who do not understand the role of an adc in the game of league" is quite wrong. A good adc must be able to kite, cs well, and have perfect positioning in a teamfight, particularly knowing when to kite backwards, or go on the offensive. Ezreal requires all of these attributes.
As for you saying it leads to the most cancerous imaginable, if you don't mind, a bit more explanation would be helpful please and thank you.