On page 48, the linguistics focus doesn’t mention anything about bonus languages.
On page 88, the polyglot talent grants three additional languages of your choice.
However on page 78 it says you have up to three additional languages if you have the linguistics focus.
Is page 78 incorrect?
I’d also be keen to know the answer to this question.
At present, I’d be inclined to allow the PC to have additional languages for taking the Linguistics focus, over an above those gained through a high Reason, the Polyglot talent or character nationality.
If you want to have a game that does a bit of globe-trotting then there needs to be a way for PCs to gain additional languages. Otherwise the humour of trying to make themselves understood will become very boring very quickly (in my opinion).