I just read the original link. I note the following:
1) it was dated April 1 and is clearly an April Fool's Day joke. It should be treated as such.
2) no nation can 'copyright' versions of its soldiers, tanks, warships or anything else. The Copyright Act of 1981 (UK but in-line with European legislation of the time) only covers intellectual or artistic copyright which belongs to individuals, organisations and companies. Governments cannot prevent scale models of anything of their nation under this legislation.
For example, if you copied another manufacturer's 'French Napoleonic soldier' that manufacturer COULD sue for copyright infringement of their sculptural work but the French government would have no interest.
Likewise if you modelled a 'Ferdinand' tank destroyer you would not have Porsche coming after you about the model. Or the German government. But if you bootlegged another manufacturer's model of a Ferdinand then they can both sue for damages and (under the Copyright Act) call in the police as an act of theft.
This is the same law broken by people who sell bootleg copies of DVDs at boot sales. It is both criminal and civil law.
There are real issues about making modern copies of combat aircraft and I note that some modern Spitfires and FW 190s were built in 75% or 90% original size and flown as a 'model' to prevent copyright infringement claims by the original manufacturer. In other cases a modern replica has been rebuilt (allegedly) from crashed parts but, in practice, virtually the only thing that is original is the manufacturer's plate. The rest of the aircraft is pure replica. This also appears to circumvent copyright claims by current manufacturers as the restorers will simply say they had to replace 'many' parts to make the type safe and airworthy.
In practice Brexit will have little effect on our hobby in the short-term, in the long-term it might effect retail prices between the UK and Europe (perhaps negatively) and retail prices between the UK and the rest of the world (perhaps positively).
Barry