While I appreciate Brexit hasn't happened yet there's little to no evidence yet of any exodus of highly skilled workforces. London remains an incredibly attractive destination for inflows of both investment, workers and tourists. Will some companies leave, no doubt, however the high profile mass departure of European HQs and banks has yet to bear out.

To the OP, and going back to the article, a major issue is that of services, our major export. The EU does not have a single market in services, and has shown little interest in progressing it. It isn't so much Deutsche Bank as the mittelstand that demonstrates that the EU as a whole favours particular economic systems. Italy is a prime example of a sclerotic services sector that their own government has failed to reform, despite the EU being willing and able to influence the appointment of Mario Monti it isn't willing to impose a free market in service in the same way it has for goods - and stand up to blatant protectionism.