Using IMF nominal, non-PPP adjusted GDP per capita in USD. For 2021, Poland was 23,014 and the UK’s 51,075.
@ed rough calc: according to IMF data, Scottish GDP per capita including oil revenue is $48k, UK average is $51k. So if anything, Scotland leaving would increase nominal GDP per capita but as I said, since the difference is small, unlikely to be a factor
@ukaszBartoszcze those calculations are based on the assumption that everything else remains the same. We do not take into account what types of economic activity would be disrupted with those steps. When a country dissociates from some association or larger country, both remain weaker. That is what happened with brexit (https://www.bbc.com/news/business-59070020 ); who knows about northern ireland besides scotland as well .. .. .