84% of the UK population live in England and are represented in Parliament by English constituency MPs
It's perfectly fair as long as you don't live in one of the countries that are almost entirely ignored. The UK was meant to be a union of equals, not Wales/NI/Scot being treated as part of the Empire.
Wales, Northern Ireland and Scotland are constituent parts of the UK with the appropriate representation in the UK parliament. In addition to that, they have something the English don't have - their own national parliaments/assemblies where issues that relate purely to Welsh, Scottish and Northern Irish matters are discussed.
I would also point out that LEAVE won the EU referendum by 1,269,501 votes.
In Scotland 1,018,332 voted to leave the EU. In Northern Ireland 349,442 also voted to leave. Those combined votes enabled LEAVE to win the referendum. Without those Scottish and Northern Irish voters LEAVE would not have prevailed.
Wales as we know, voted almost 53% in favour of LEAVE.
Leaving the EU is far from an English decision inflicted on Wales, Scotland and Northern Ireland. Every UK citizen in all regions, was given a vote, and significant numbers of them wanted out of the EU, including over a million Scots.