UK firms follow the general European trend in diversification, namely reducing it. Their approach to internationalisation is, however, very different. In contrast to their European counterparts they look for markets primarily outside of Europe. Clearly, they are not as impressed by the opportunities created within Europe.
The EU common market has helped stagnant, state-supported European industries gain a competitive advantage within the European market over their non-EU rivals by subsidising inter-EU trade (aka removing tariffs on European goods while keeping them on non-EU goods). Other than that Europe has served no useful purpose to trade, and is so uninspiring that even with tariff-free access to Europe British firms have still looked further overseas for their international opportunities.
It's time to ditch the bitch and set sail for the new world!
The British public clearly agree, with their happiness and wellbeing rising markedly since their momentous decision to escape the EU: