I think Portugal has inherited a lot from the Arab countries. They brought their nostalgic songs because of the wars. The Portuguese like to sing or listen to the “fado”because for them to remember past things is a therapy.
I am a Portuguese citizen born in Africa and I admire African people for feeling happy and laughing even in times of difficulties.
I think I've inherited this from Africa and I never remember the sad things because they are not a therapy for me.
Moreover, Portuguese people in recent years are very mixed; I have no idea what will make them sad. In the villages, the retired old guys and the very young people maybe they become sad when Cristiano Ronaldo is not the best or when Portugal did not win some soccer game.
And what can make a Portuguese sad about a foreigner?
In reality the Portuguese are hospitable and have a very good quality of service.
I owned a small hotel of charm in the city of Coimbra and we did everything to receive well, but some Europeans were very demanding and when they did not tell us what they needed and instead sent negative comments to the Booking, of course this made us sad. Really,
I do not know what the questioner had in mind when he thought something could make the Portuguese sad! What I know from other countries leads me to think Portugal is a blessed country when I make comparisons with what happens in other countries.
True is that there are not many bad things to make the Portuguese sad!