M&B didnt have religion before. Not in Warband and not in previous versions, if they were to add religion all of a sudden whole lore would have to be changed and it wouldn't make sense with Warband at all. Bannerlord takes place in 11th~ century while warband takes place in 13th century. We dont have a single indication of religion in warband so what, after the collapse of Calradic empire everyone went ateist? It wouldnt make sense and would destroy the lore.
In the warband, we could not use throwing machines and one person could move the siege tower. And it turns out that after the disappearance of the Calradian empire, everyone became strong, but stupid?
Without religion, we certainly don’t lose much, but you are talking about all of these opportunities as something bad. Crusades and jihadis awesome opportunities for role play and climbing the career ladder, started as a soldier, and ended the campaign with a knight of the Order of St. Harlaus)