GBR are still haunted, I think, by the twin spectres of Atlanta 1996 and Eddie the Eagle Edwards. Most cuontries didn't care how GBR did in Atlanta, but in GB it was a national humiliation at the tail end of a government that was itself a kind of by word for a national malaise, while Eddie, while popular, was also deeply cringe for a country that wanted to be taken seriously, but increasingly just wasn't.
In the last few years, GB was supposed to have relaxed a bit from the frightening level of ruthlessness that the new era created - the success of GB in new sports has come at some cost in terms of ethics and athlete welfare with a series of scandals in cycling, swimming, gymnastics, bobsled etc That monomaniacal push for medals seems to have reduced a bit, and I personally expect the medal count to reduce significantly as a result, but one place it seems to continue to hold is selection policy (tight purses is also a factor ) with a series of perfectly respectable international class athletes set to miss out, including a couple of youngsters who might be world class soon (the two hammer lads spring to mind here)
IMHO it is ridiculous. And it particularly annoys me when Australia and South Africa do it too.