* CDR used to be more scarce, so blocking a spell used to mean you couldn't get hit by it again for a while. Now, you see everybody but ADC's hitting 40% CDR whenever they feel like it, so blocking that Morg Q just means you get to wait a couple seconds.
* Damage used to be somewhat reasonable, so blocking a spell meant you didn't die in one rotation. Now, blocking one spell doesn't matter since they're overkilling you by several hundred HP anyhow.
* If your dodging was on point, you used to be able to save your shield for something that mattered. Now, even if you don't get hit, you can still lose Banshees because Ludens splashed on you.
* Not only is it a 40 second CD, it's 40 seconds of *taking no damage*, which is just a *bit* high.