If there is one thing I can say with confidence about Britain it is that we like having several and/or confusing names for our country/countries/
flag/flags.
We still have the best looking flag in my opinion though!
PROTIP: I found a good way to tell if someone is actually British the other day. I downloaded a podcast hosted by an American guy with an American accent who, when talking about Britain said "I'm actually a Brit myself". That sentence is an oxymoron as using the word "Brit" is cast iron proof that the user is not British.
It is like me saying "actually I am a USAian", no American would say that.
There may be many names for the British, but we get to make them up, our language, our rules!