I'm in the minority when I say this but I personally don't mind the change. I want to mention some points and also some suggestions to possibly please everyone while keeping the game immersive.
Why I like it the way it is:
The way it is now, for me it marks the end of the battle so I can tell quicker that it has ended when I can no longer order my troops. This change also slightly nerfs cavalry and archers because they're the only ones you can use to catch routed units to farm exp and loot, and this only makes infantry worse than it already is, giving archers and cavalry a huge advantage specifically when farming exp which is already very easy for ranged units especially. It being this way also immerses me because realistically after a battle there will be disorganized behavior between the troops from excitement/adrenaline/and greed to loot the dead, and it's further more immersive because this is also marked on the campaign map after a battle by a reduction in movement speed through the debuff "Disorganized", so for me it makes sense overall.
All things considered, I personally like it the way it is. But I've never really felt the need to put my troops in order for a screenshot or other things players like to do after a battle. All these reasons considered, I can see why TW also likes it the way it is now.
As for suggestions:
1. There should be more variety of actions soldiers will take, for example crouched "looting" animation over a corpse (only if corpses are enabled for the player). That way some would be cheering, some would be looting, some would be chasing the last enemies, bringing more variety and immersion.
2. Make a key responsible for "retaking command" of the cheering/looting units so you regain control of the troops. Yes, this is what a "bastard" commander would do, and some players want to play that way. But this shouldn't happen without some morale penalties. Battles should reward less morale if you don't let the soldiers just do their thing after a battle as they realistically would after putting their life on the line for you. You should also gain some sort of negative trait by not letting them cheer and loot. Moreso, maybe bandit units wouldn't suffer morale penalties (this can be a perk effect in roguery), because they're 'bastards' anyway. This can definitely go more in-depth. PS: still waiting for the perk to allow us to recruit a big amount of bandits (over the troops limit).