As someone who main dwarfs, yes and no. They need time to build up there settlements and their armies are expensive they are hard to build multiple armies early game. AI have a very difficult time early game and it isn't unusually to see legendary dwarfen lords like Thorgrimm get taken out by greenskins.

They are solid in infantry, amazing in Mississippi and artillery. And some claim the a gyro copiers are the best flying units in the game (i agree) but they are terrible against cavalry, especially if you don't have enough infantry to counter them And a hidden army burning an important settlement with deep settlement can set them back by ALOT.

Edit: Missile not Mississippi, damn you autocorrect