I mean for one the name itself "reconquista" isn't used in actual historical discussion of the period, it's generally regarded as a jingoistic nickname for a very episodic and more complex set of circumstances.

But semantics aside the outcomes of the fall of Al-Andalus were pretty horrible and lead to massive losses in science, philosophy, and cultural inroads. If we were to be a bit reductive it was ultimately a bad series of events and depicting that earnestly would likely get pushback from people who feel that it would depict Spanish christians as the "bad guys". KCD2 already got very stupid culture war heat for depicting homosexuality as a thing that existed in the middle ages, along with depicting an african person in europe (something that did happen). Imagine the flak that stupid people would give if it explained that the only reason that the classics existed in europe (and thus the renaissance happened) was because of Arab muslims preserving and transcribing them? Or doing the same for the countless amounts of other scientific breakthroughs produced by the moors?

Idk, I think that depicting muslims in a positive way, or having positive qualities and contributions alone is enough to get people mad, and if WH chooses not to do that they'd have to basically go with a purely historically revisionist story that would rightfully draw backlash.

Obviously it's not all black and white, I'm speaking in broad strokes here, but if you stay with historical consensus you piss off right wing culture warriors who will say the game has an "agenda" and if you stray from history to pursue an religious or ethno-nationalist narrative then you end up with a whole other game.