If they understand what players want, they'll add it in a patch/DLC or as part of a "definitive edition".
I gotta be honest here. If they put this on a Definitive Edition that requires me to buy an entirely new copy of the game, or else pay "extra" to upgrade my current version to Definitive, then I will never buy a game they've worked on again, unless it's on a steep discount/sale.
Can forgive a lot of things, but a feature like this, which should have been in the game from the very beginning being plopped behind a paywall, is absolutely ridiculous.