It may not make sense to you, but they've been arguing constitutional law there for hundreds of years.
Plenty of monarchies also have modern single-document constitutions, like Norway, Spain and Thailand.
(Canada had previously deferred its assumption of the power to amend its own constitution without asking the UK to do it until it figured out what replacement arrangement it wanted, which took half a century and the requesting Canadian government still very controversially did not win the assent of or even consult Quebec before proceeding.)
With that said, there is an important structural difference: Canada is a true federal state rather than a unitary one like the UK which merely has some nonexclusive and constrained devolution to three subordinate parliaments within specific scopes. Every single bit of the Canadian constitution is indeed freely amendable by enough of the eleven Canadian federal or provincial parliaments working together. Certain specific parts can indeed be amended unilaterally by one parliament, but many parts need a much larger level of consensus, up to and including unanimity.
This means that the Canadian situation is not really a counterexample to the claim that the UK parliament would necessarily retain full amendment rights if it did codify a constitution, since the UK parliament is most similar in authority not to the Canadian federal parliament but to all eleven federal or provincial Canadian parliaments combined, which collectively do retain full amendment flexibility if they can all agree as required.
However, some provinces refuse to ratify amendments without a referendum, and the country has a lot of trauma from past failed attempts to make major constitutional amendments such that they mostly don’t attempt them any more, so the eleven parliaments have de facto lost some of their collective parliamentary supremacy even if they have not lost it de jure.
> The United Kingdom constitution is composed of the laws and rules that create the institutions of the state, regulate the relationships between those institutions, or regulate the relationship between the state and the individual. These laws and rules are not codified in a single, written document.
Source for that quote is parliamentary: https://www.parliament.uk/globalassets/documents/commons-com... - a publication from 2015 which considered and proposed a written constitution. But other definitions include unwritten things like customs and conventions. For example:
> It is often noted that the UK does not have a ‘written’ or ‘codified’ constitution. It is true that most countries have a document with special legal status that contains some of the key features of their constitution. This text is usually upheld by the courts and cannot be changed except through an especially demanding process. The UK, however, does not possess a single constitutional document of this nature. Nevertheless, it does have a constitution. The UK’s constitution is spread across a number of places. This dispersal can make it more difficult to identify and understand. It is found in places including some specific Acts of Parliament; particular understandings of how the system should operate (known as constitutional conventions); and various decisions made by judges that help determine how the system works.
https://consoc.org.uk/the-constitution-explained/the-uk-cons...
Just because it isn't 1 document like in the US, it doesn't mean it's not a constitution.
I think what you mean by "contemporary connotation" with "American connotation".
The most likely outcome by far at this point is the continuation of disconnection from European institutions by leaving the echr. In effect this would mean the rolling back of parts of the British constitution. It would be a good thing because the equivalents of the American Constitution are much more vaguely written, and in practice do nothing to protect anybody's rights whilst allowing left-wing judges to rampantly abuse their position by issuing nonsensical judgments that advance left-wing priorities. That's why reform and Nigel farage have been pushing for many years on leaving the European institutions, which is in effect a rollback of the Constitution. And this position is very popular.
Indeed, the founding fathers of the US identified political parties as a threat to their republic.
