So outside of the UK people often falsely use GB, UK and England synonymously (sorry Wales). Similar to how people call the Netherlands Holland, although that is just one part.

I think at some point people should just accept that the meaning has decayed completely and GB/UK/England means the lower half of the island on the right (up to Scotland). Maybe introduce "BI" for "British Ilses"? Unfortunately, .bi is already taken as a TLD.