You can say that about anyone, and even sacred words will be used to curse them, so what's the point?
Imps are much better than in Might and Magic III. And that's it.
And they are more useful than many others. Specifically, with their flight and blocking archers. Well, yes, they also drain mana from neutral creatures. And they can fly far across the map, which is very helpful for gathering resources. So, I don't understand why they are disliked?
1. Weak (in every sense - low health, low damage).
2. The most pathetic monster in the concept of the Might and Magic IV developers.
Personally, I would prefer 50 Imps, 50 Troglodytes, or 50 Pirates. But not 50 Fairies or 50 Archers.