I, personally, find there to be no reason to remove the Fear of Gremlins creature from Monstrology. It follows the two main Monstological guidelines, which are:
The creature must be repeatable, which it is.
The creature must fall into a Monstrological category, which it also does.
Removing it from Extract Imp is completely pointless and actually makes the spell almost worthless, because we would be left with only six creature in the category, five of which look exactly identical. The Fear of Gremlins is basically the most unique creature extractable with the spell. If anything, the category needs to be expanded instead of reduced. Please let the Fear of Gremlins stay.
Theyre wanting to make that more of a scam? Extract imp is absolutely horrendous, even for decoration, because the monster imps are barely larger than pet imps.
They did say they were considering adding Grendels to Extract Imp. I certainly think it's a good idea. I see no reason why they would remove the Fear of Gremlins, it's such a waste of time. And could they add the Grendels, too?