Ezreal has been my favorite Champion since day 1 of his release - and CDR is not what is holding Ezreal back. Ezreal has always had short CDs to begin with and he gets more cooldown reduction from landing his Q then he needs from CDR. He is already spam-happy.
What holds Ezreal back is 1) lack of kit cohesion, 2) outclassed mobility and 3) lack of late-game scaling.
Kit cohesion is basically just that AD Ezreal doesn't even need W (its great for pushing down objectives, but in early-mid its nothing), while AP Ezreal doesn't really get anything out of his passive. Speaking of which, his passive pushes him towards moving into AA range, but Ezreal has one of the lowest base MS in the game, 0 cc, only mobility is E, and he just doesn't scale into a hypercarry. So he can't duel ADCs 1v1 at close range, yet he has an AS steroid on his passive. Ezreal used to be considered "high mobility" but with the increase in mobility across the board he falls behind. The only saving grace is that his E is a godly blink and he can burst its CD down through his Q.
Late game scaling - Ezreal doesn't scale with crits. he doesn't build it often (TF just happens to have crit chance, and he can build IE, but that's usually it) and Q can't crit. He isn't an AA-focused ADC so he doesn't scale with a crit build. However, other hypercarries have what I call "alternate damage sources" that help them scale into the late game. This is Vayne's Silver Bolts or Kalista's Rend stacks, which let them focus on AS over Critical Chance. Ezreal doesn't have a late-game damage boost to let him take down targets in the same way as other ADCs.
Then there are the item changes.
ER was supposed to become the key item for AD Caster Marksmen. They're changing it to have CDR scaling with.. Critical Chance?? As I mentioned that's not really a useful direction.
And TF? AD was lowered, AP was removed, AS lowered, MS was lowered. The only things that went up were CDR, Mana, and Crit Chance. Which Ezreal doesn't need. Granted there are more Champions than Ezreal who wants to build TF, but these changes don't favor him.
Now that said, there are a ton of new items and updated items so I realize that I can't really say whether or not he'll find a new core build; but I think they're focusing on the wrong areas. They're focusing on all this CDR stuff, even increasing Q's CDR reduction. But W remains useless and Q practically refreshes itself on hit. So what exactly is he supposed to do with all this new CDR? Okay, he'll get his E/R more often. A buff without a doubt, but still not what Ezreal deserves.