But the parliament could, by a majority vote, simply abolish the SCOTUK, or modify any of the precepts of its constitution by a similar measure. Constitutions can always be amended, even ii places with strong constitutions like the US, but it is much more difficult than a simple majority vote.
The "people" are an important component of the British Constitution, and this component has historically exercised its own check over the various branches of Government, not only by the ballot, but by public demonstration, open revolt, and full-blown armed rebellion. A Parliament that modified the Constitution in open defiance of the will of the people might very well face more than electoral defeat at the next election.
In fact, Parliament's fear of the peoples' power has led it to make compromises that have seen Britain mostly avoid the sorts of large scale, metropolitan-wide disturbances that racked the Continent in recent centuries (e.g., The French Revolution, The French Terror, the revolutions of 1848, the French and Russian Mutinies of World War I, the socialist takeovers of the 1920-30s).
I would argue that the U.S. Constitution may be one of the worst written constitutions in use today. It contains very few particulars and speaks in generalities that not only invite, but down right require, judicial review. The U.S. Constitution mandates, for example, that laws originate in Congress, instead of the Executive Branch, which means all national legislation is composed by Congressional committee. This results in laws that contain so many compromises that legislation often contains verbiage that contradicts other verbiage in the same law; and clauses so vaporous as to be nearly (but not entirely) devoid of meaning. Parties who suffer losses from the way these laws are implemented can easily find support for their positions in other parts of the very same law, which gives them standing to sue. When the Supreme Court rules on how these bad laws are to be interpreted, legislators scream "activist judges", even though it was these very same legislators who delegated their legislative authority to the courts by writing such poorly drafted laws! (Most legislators are attorneys and know what well drafted laws look like, which leads one to believe they intentionally delegate their authority to the courts because they are too craven to take political responsibility for their legislative actions.)
. Processing times hopefully will stay short for a while.