What do any of those things have to do with the EU? Brexit supporters are in favour of more global trade with countries like China, and lower environmental and labor standards. They hated the EU because it was precisely the opposite: A self-sustaining trading bloc made up of mostly successful, developed democracies, with (relatively) strong regulatory protection for workers and the rule of law.

Corporate interests know that, in a struggle, size is what matters. Multi-national corporations can effectively bully the governments of individual countries far more easily than they can a supranational collection of governments who resist being played off against each other. Faced with a lack of success forcing the EU to deregulate, these interests have instead switched to trying to undermine the institution itself, by funding populist campaigns that blame economic problems on the EU, even though it was under-regulation of finance (championed by the UK) that lead to the 2008 crisis.

A break-up of the EU will lead to outcomes a thousand times worse for poor and working class people throughout its member nations, and consequently around the world. There will be a race to the bottom in terms of regulatory protection and labor rights. There will be massive declines in average standards of living. There will be a rollback of democracy, as strongmen and autocratic governments re-emerge in Europe. There will be a return to war between European states, and pogroms and ethnic cleansing as nationalist governments cast around for scapegoats for their own failure.

If you think the pre-Brexit economic model had "serious faults" then believe me, you ain't seen nothing yet.