I do know he was the son of god, but he was not a god
I don't think anyone was suggesting Jesus was a God? Good Friday is important because, as the son of God, Jesus made the ultimate sacrifice to save the world from sin. That is the Christian teaching. Of course, not everyone believes this, but in a country with Christianity as its chosen faith, the holidays will be organised around these dates. Personally, although I am no longer a practising Christian, I feel Good Friday and Easter Sunday should be kept special for a variety of reasons, one being a chance for people to reflect, take a rest and re-fuel their batteries.