Where did you hear that? It's not true at all...
I've read it here before I made my post, it's on portuguese tho so not sure if you guys will understand it.
I've been searching now and I don't find that info anywhere else, in fact I've gone to the PS App and I can apparently buy PS4 Director's Cut expansion indeed, even as I did not buy it to confirm the fact (tho I got to the payment screen without a problem).
So now the problem is having to pay it twice to be able to play it on PS5... seems like I can still play the game in this new version for free through BC, just won't be able to get some improvements, like the japanese lip sync, which would be great...
Well, it's less sucky then I originally read it was, the pricing is quite high tho, but that's a problem with all new games around here right now, the pricing is just absurd. It's BRL 104 for the upgrade, and I've paid 200 for the full game at launch (Basically paying as much as the PS5 upgradr for the PS4 upgrade).
Will look out for some big sale in the future if the content is good.