Can someone explain why Veigar's getting double nerfed?

I want to start off by saying that I understand and agree with the DFG removal, and I haven't been opposed to any of the resulting changes I've seen on other burst mages that have been reworked in one way or another either.

But why go after Veigar so hard? The Q change is good, and seeing that I understood the ultimate's AP scaling nerf. I'll even concede that a giant ring that shows up instantly and stuns champions for 1.5-2.5 seconds is overpowered in any context. However, 0.75 seconds is too long of a delay to be adding when the skill doesn't do damage, it will now be next to impossible to land, causing remaining Veigar players to hug their towers more since they no longer have kill potential on anyone with mobility in a meta where mid lane is ruled primarily by ultramobile assassins. I would have gladly accepted a 0.5 second reduction at all levels of the stun (then 1.0-2.0 seconds), and a 0.25 second delay reduction on E (making the delay 1 second) or something to that effect.

So please explain how removing the only mechanic keeping Veigar remotely viable is a good change after removing an item that was almost 100% necessary for the champion.

TL;DR Play AP Blitzcrank until they start giving you 0.75 seconds to walk out of his fully extended rocket grab because his laning is 'too strong.'