If you look in ElementalDefs.xml, you find this:
<OwnershipTurnsBeforeCanRaze>5</OwnershipTurnsBeforeCanRaze>
So presumably if you did want to try playing with insta-raze... just change this to zero and you're probably good to go.
I think the key thing is that it should be consistent i.e. same for AI as it is for the player. Frogboy all but admitted it was a bug in another thread, this one:
https://forums.elementalgame.com/439893
In fact reading that again now, he actually said "It's on my list.", so hopefully it's still on his list because this one has been complained about quite a bit.