And in that case, Brexit can be proven to be working well for Britain as the country will not anymore be dragged by the weakness of Euro
UK never used Euro. UK uses GBP. They were never really part of EU. It was the last time for them to decide if they want to be in or out. Being a bit in and a bit out was dragging EU back for decade.
Yeah, an European Federation would be bad news but I doubt it will ever come to that anytime soon. The EU is going through too divisive times for such measures.
Strong EU federation is the only hope Europe have. Every single country is nothing alone compared to strong India, USA and China. Together can compete. EU need to develop space and military program together. All hi tech technology. No use that every country research its own battle tank or fighter jet. No use if every European country send a spaceship to mars. Together we can!