You quoted my entire Post, but then only commented on the last short sentence. (And while I am not condoning it, some might consider a £480 addition to the cost of a well needed holiday to be worth it!)
Now try commenting on the rest of that entire Post that you quoted?
(And just to add to that it appears that the Belgian government is ahead of the UK governments by being more 'area specific' rather than being 'country specific', meaning that people travelling from Lisbon requiring quarantine could/should free up travel to/from the rest of Portugal.)