If you run things efficiently you're eaking every ounce of performance out of this hardware. A 30% performance hit means a 30% cost increase.
The bigger issue is for things that don't scale easily. That sql server that was at 90% capacity is suddenly unable to handle the load. Sure that could've happened organically, but now it happens (perhaps literally) overnight for everyone all at once.
Expect a bunch of outages in the next few weeks as companies scramble to fix this.