I think pps are being a little unkind about British traditional cooking
Very much so, regional traditional cooking was as good in the UK as in other places. Most peasant cooking in France or Spain or India was not full of exotic things from far away and more than in the UK. Up until recently people ate locally and seasonally. And the really poor have always eaten poorly, everywhere.
British cooking did suffer due to war rationing, and then people coming out of it were suddenly inundated with packaged foods, at the same time lifestyles were beginning to change. Manufactured food was seen as modern, and then as women began to work more and there were other social changes, a certain cooking skills and traditions were, not wholly lost, maybe, but compromised.
That being said, curries were common even in Victorian cookbooks, as well as dishes inspired by other British colonial traditions, so it's not wholly new to have that kind of introduction from abroad. Spag bol and appreciation for pasta generally came from soldiers who had been in Italy. But because shipping meant the same products were not available they tended to be adapted to local ingredients.
I do find it amusing though that with all the fussing some younger people make about older people not living in an environmentally sustainable way, the same young people tend to be rather superior about the global trade and travel that means their diets as a whole are much more varied.