Why is Ezreal considered the safest ADC?
I honestly don't believe that he's the "safest adc" just because of his blink. Kalista can kite, Graves can dash through walls, Twitch and Vayne have stealth, and Jinx has 700 range. Ezreal is the last champion I would call 'safe'. He basically has a second flash with an absurdly high mana cost and cooldown. And that low HP really helps him survive ganks. But yea, I guess ezreal is the safest adc.
WAY too much of Ezreal's power budget is in this ability. In a game with Infinite mobility, Ezreal is not that hard to catch. And if you don't have free mobility (Nidalee), mobility boots aren't that expensive. His blink really doesn't do that much for him.
item, so mana isn't an issue. His passive grants built in attack speed makes for easy harassment/kiting. His Q has a fairly long range, low cooldown (including decreasing it's own cooldown and the cooldown of all the other abilities. .. I can't stress cooldown enough), the static cooldown is pretty much exactly 1 second less than the expiration for stacking his passive, it has low mana cost. His W is a pass through skill shot meaning he can harass while hiding safely behind his minions. Also grants attack speed to allies making him a great champion to lane WITH (teamwork for the win!!), and the massive AP scaling makes it a very punishing ability. As you mentioned, the most obvious "safety" is his E. He can jump to dodge skill shots, and over most walls. This is clearly a great disengaging tool, but something most people don't consider as an addition to his "safety" is how much this adds to his ability to quickly engage and deal a massive amount of burst damage. Lastly his R, ... It's global, .. it doesn't get any safer than that.