The verse you cite Phil is a defunct one that has almost certainly never used for some considerable time. It represents an attitude which has almost died out with the dinosaurs. Like it or not it is still the official anthem of the United Kingdom as a whole and the tune is also the Royal Anthem of Norway, of Lichtenstein and they even sing the tune in the USA! My Country T'is of Thee.

The number of people who know even the second verse these days is considerably limited. There are many verses of songs that have been dropped with time and words get changed. Even if one chooses not to sing the words, the tune is the same.

The idea of Country anthems within the UK is of more recent antiquity. The Wales anthem Hen Wlad Fy'n Hadau is nineteenth century and the "English" Land of Hope and Glory (this is still considered Brit in some circumstances) early 20th. Heck Scotland the Brave as a tune is early 20th and the words from the 1950s and Flower of Scotland even later though its popularity over other candidates is undisputed.

As to the flags - I saw very many in Wales and media coverage showed them in Scotland also. Maybe they only came out for the cameras?