No, it hasn't been fixed, but the bug isn't that new units don't receive the promotion, it's that medieval units keep it when they are upgraded to a Renaissance unit

. Only the Almogavers must keep it when it is upgraded to Commando.
The UA say :
OK, while writing it I realize that it is not very clear

.
I really wanted to mark the passage from an era of conquest for Catalonia under the Crown of Aragon to a more withdrawn era under the Crown of Castile then an economic and cultural revival at the beginning of the industrial era through the Sagrada Familia and the many GPs that arrive.
The second reason is that this promotion becomes powerful on the other side of the world, so it disappears in the era where units can be thrown very far.