The EU is flawed and in today's era absolutely useless. When it was created, sure there was a purpose and a need however such need has diminished. The rest of the EU needs to actually develop a plan now to dissolve the EU gracefully without causing mass panic with the markets.
The EU nas the same need as it has when it was created, even more then it had back then. The small european countries has to stick together or else they'll get swallowed by the economic tigers on the global level, that didn't really exist back in that period(as economic tigers)
The problem is, that it needs to be exactly what it was back when it was created as the EEC(European Economic Community), without the political and specially without the heavy Brussels birocracy part that's the biggest problems everyone have with, when it comes to EU(main reason Brexit leaders pointed out for their opinion).
I'll take my country as an example, Serbia is the candidate for joining the EU(it was suppose to happen until 2020 for sure, but now who knows), and even tho most of our export goes to EU countries, and it was mostly USA/German/Italian firms investing in Serbia since our path to EU, China, Russia, and Arab countries has massive projects of investing in Serbia last 2-3 years and specially in the next 10 years, not only taking the position of EU countries when it comes to investing, yet investing in huge projects that EU countries never really wanted to 'risk' when it comes to Serbia.
Serbia as a candidate has the benefits from the united market with EU on one hand(SAP agreement), yet it has a non-custom trade agreement with Russia for decades now(the only country in Europe to have such a thing), which will have to be canceled once Serbia joins the EU.(Because you can't be a member of the EU, and have non-custom trade with Russia in teh same time)
So investing in Serbia at the moment, is highly recommended for big global tigers, as they can export cheaper not only into the EU market, yet on Russian market as well. Plus Serbia is one of the rare fully stable countries in the whole region, so its a perfect place for a base of China's/Arab/Russian capital in Europe.
But the point is, EU countries are losing their economic influences in Serbia, and that means losing political influences as well, and that again means losing influence on Balkan, since Serbia is the biggest and central country of Balkan, if EU collapse, that influence is doomed, and Germany/Italy/France and the rest of them, are gonna lose a big market just next doors to them, which they cant allow to happen.
Because all of this EU will prevail, it just wont be an organization it was til now.