Rest assured, there are plenty of numpty's flying in the Uk and Europe, both at PPL and airline level. When I was instructing, I worked alongside a couple. The NZ ego thing is true, but some Poms have a far greater ego problem and in many cases much less experience.
The differences are simple: the amount of GA in NZ compared to UK, per capita; the fact that a light plane crash in Britain is not really big news (in fact it amazes me that any plane crash here is news for 5 seconds and is lost in the sheer volume of other news, whereas in NZ it would linger for weeks); the volatility of the NZ weather combined with unforgiving terrain; the lack of airports in NZ to sprint to when things turn to custard (there are simply hundreds over here); the comparative lack of uncontrolled airspace in the UK; etc etc.
LOST