I don't have this faith that it would take several Parliaments
Much of our Constitution is blurred, with many safeguards not being irreversible
and depends on a govt - when it has a large majority - feeling morally constrained not to use their full executive powers.
Blair's bloody Civil Contingencies Act 2004 horrified me at the time, but hardly anyone would listen.
He wanted full power as always and was wilfully blind to the possibility that the far right / left could come to power and use it
Parliament is supreme and a large hard right majority, especially in a BREX coalition, could flood the HoL with new peers and dismantle the judiciary in one, if sufficiently determined
MrsT wanted economic & social change, so concentrated on that; the transformations she made in the 1980s were massive and have become permanent
However, removing & replacing judges, changing the court system are defined actions, hence much quicker than radical economic change.
All that has stopped previous large majorities from going
I was surprised how quickly Blair could bring in radical constitutional changes like a Supreme court
and a Scottish Parliament, a Welsh Assembly (NI is a separate case, with special circs)