Nival does what Ubisoft ordered them to do, this has already been mentioned, meaning written.

Well yes, of course they have absolutely nothing to do with it...
They are just the developer after all... :D
I can practically see Ubisoft giving orders to Nival:
-No more than 40 spells
-No more than six on a spellbook page
-Battlefield no larger than 8*10
-Must deviate from canon and make combat non-turn-based
-Under no circumstances create more than six Castles
-There should be no Orcs in H5, otherwise people won't buy it...:D
-A horse as a cursor is unacceptable
and many, many other things...
As if they have absolutely nothing better to do...
And the way Nival denies their own shortcomings by shifting the blame to Ubisoft—that doesn't interest me...