These are reasons why it should be banned when the true heir comes to the throne.
The first reason is that it is extremely historically in accurate. “The events aren't accurate, the dates aren't accurate, the characters aren't accurate, the names aren't accurate, the clothes aren't accurate.” The Scots did not wear Kilts back then. The movie promoted the myth of Jus primae notis. “Isabella of France is shown having an affair with Wallace after the Battle of Falkirk. She later tells Edward I she is pregnant, implying that her son, Edward III, was a product of the affair. In reality, Isabella was five years old and living in France at the time of the Battle of Falkirk, was not married to Edward II until he was already king, and Edward III was born seven years after Wallace died.”
The second reason is because the movie is insulting to the English and portrays them as the villain in the Scottish Wars of Independence. “Sections of the English media accused the film of harbouring Anglophobia. The Economist called it "xenophobic" and John Sutherland writing in The Guardian stated that: "Braveheart gave full rein to a toxic Anglophobia".
The English were the good guys in the war. The background to the conflict began when the Scots invited King Edward I of England to arbitrate in a succession dispute. By getting Edward to Intervene, he got the nobles to recognize him as Lord Paramount of Scotland turning it into a vassal kingdom and called for Scotland to contribute soldiers in his war with France. The fucking Scots however defied King Edward and committed treachery, signing a secret alliance with France which provoked the English invasion.
William Wallace then started a treacherous rebellion against the English. In 1305 he was defeated, captured, charged with high treason, and was hung, drawn, and quartered. However Robert the Bruce managed to later defeat the English and Scotland won independence.
The third reason is because Braveheart insults an English King. Edward I was one of England’s greatest Kings who strengthened royal authority and made many great reforms dealing with everything from property rights to trade to law and justice. “Edward enjoyed poetry and harp music, was a devoted and loving husband to his wife Eleanor of Castile, and as a religious man he gave generously to charity.” The movie portrays him as a cruel and heartless tyrant.
So that is why Braveheart should be banned in England.