Once when flying on TAM I had an emergency seat on a domestic flight from Recife to São Paulo. Spotting my gringo skin the flight attendant challenged my knowledge of Portuguese in English with the explanation that if I didn’t speak any Portuguese I had to move. She was surprised to discover my response in Portuguese but what she didn’t check is the two Chileans to my inside who did not speak Portuguese and barely understood any English. To be honest at the time I find amusingly ironic but aftewards realised the potential risk of the situation. I do feel sorry for the cabin crew as it is not them who booked the seats, checked in the baggage or pass check at the gate but they are left to resolve the problems.
On International flights though I have never seen TAM enforce the Portuguese speaking regulation including on the 767s which have over wing exit doors. Perhaps only applies on local flights