Oh, please. With or without Scotland, England remains in the lead or on a par with the other most advanced countries in the world in most areas. Of course it has it's problems - like everywhere else - but the downturn that was forecasted to begin immediately after a leave vote has not materialised, with the UK economy proving remarkably resilient in this post-leave/pre-Article 50 period. If we judge it by the wisdom of crowds, I don't see a massive exodus of immigrants leaving the UK in fear of a downturn post-Brexit - in fact the opposite - I seem to encounter more and more immigrants everywhere I go in England, so no doubt they judge that your sinking ship is preferable to life in Spain, Poland etc. If you want to see a sinking ship, look across the EU where there is mass unemployment, suppression of free speech in support of mass immigration, a failed currency resulting in destructive economic imbalances, social dislocation due to lack of integration of migrants, free movement for terrorists and criminals, nepotism, all ruled over by an unelected and unaccountable elite in Brussels.
England is still one of the most important economies in the world. Better not hope she goes down, or everyone gets poorer.