The utility tree used to give bonus stats to make up for the lack of combat effectiveness. This is no longer the case. It's not the biggest nerf in the world but it's still meaningful and quite relevant early game. In terms of gold, it's probably about like starting the game with 50-100g less when going Inspiration primary.
Unsealed Spellbook is, however, one of the most powerful Keystones currently.
At least from what I've heard.
The stats remain the same actually. All it did was give the same bonus your primary path did.
Now you can choose to either do that or mix it up.
Edit: I was wrong. For anyone like me who didn't know:
Primary/Secondary Prec/Insp = 18% AS Insp/Prec = 20% AS Reso/Insp = 270 Health Insp/Reso = 300 Health
This is pretty low of them. That isn't much gold but can matter a whole lot early game.
It was 20% AS if you took Inspiration primary.
18% otherwise.
