That is interesting!
I always thought about, if Portuguese people would like to play using Brazilian Portuguese. I guess at least some could! I remember that about 10 years ago, here in Brasil, we used to play games using Traditional Portuguese, like the first Uncharted. We didn't have that many games in Brazilian Portuguese.
Since we have similar language, I think it would be a good choice if CD Projekt RED let console players from Europe to choose Brazilian Portuguese too. This decision was probably made because Brasil is not a European country, but, this is probably something that can be fixed with an update.
Just tell other costumers that you know, to ask about it here too. Maybe using a Post for this could have better impact, anyway, I'm pretty confident that this is something that can be fixed with a patch.