This could be taken the wrong way around so, to clarify right at the beginning, we do not mean that those who don't like Brexit should leave. However, this is a good example of one of the great - perhaps not the greatest as in the headline but still hugely important - freedoms and liberties:
The number of British nationals applying for French citizenship has increased nearly tenfold in three years, France’s interior ministry has said.
The ministry said 386 Britons filed applications to become French in 2015, rising to 1,363 in 2016 – the year of the Brexit referendum – and to 3,173 in 2017. Over the same period, the number of UK nationals obtaining French citizenship increased from 320 to 1,518.
Le Figaro newspaper said many applicants were motivated by considerations such as avoiding queues at airports, the Channel tunnel and Eurostar terminals or a desire to secure rights to healthcare and social benefits after the UK leaves the EU.
But Fiona Mougenot, a British woman who runs an immigration consultancy in France, said she was handling more than 20 naturalisation applications filed in 2017, many prompted more by a wish to retain European citizenship than to minimise potential bureaucratic issues.
“Practical matters are important for our clients, of course,” Mougenot told the paper. “But for most, the primary motivation is to stay European. Many could not vote in the referendum, are horrified by the prospect of Brexit and feel betrayed. France is vital to them because their lives are here, but beyond France it’s Europe they don’t want to abandon.”
Again, the point is not that those who don't like an independent Britain should wander off. Rather, it's to point to that freedom, the right of exit. If you don't like a polity, for whatever reason, then it is essential that you have that liberty to leave it. This is true of bureaucracies, taxation systems, nations, food suppliers and transport systems.
It is, in fact, the basic argument against monopoly and in favour of competition. That you, we, are able to select the organisational system, supplier of such, which best suits our own desires.
You don't like what your fellow citizens do? So, go and commingle with a different group in a different citizenry. That is the great freedom, that right of exit, just as it is in any other quarter of life.