No, this is just upside down.

Various levels of elected monarchy have existed, but the whole reason that Magna Carta is important is that all sorts of abuses of power were going on in the name of the King and the aristocracy were fed up with it.

Given the full text, it's fairly easy to go through all the "X is not to Y" statements and work out what scenario caused that line to be in it: https://www.archives.gov/files/press/press-kits/magna-carta/... Quite a lot of it is complicated details of inheritance law and workings of courts, but you can take a guess at e.g. "No town or free man is to be distrained to make bridges or bank works save for those that ought to do so of old and by right." -> prohibition on corvee labour, people being press ganged into this kind of work.

It's mainly really, really bad history

> Each lord had a veto power over the king and over each other law (I will use the term “lord” for those landed free men. Even the serfs could not be denied their right without adjudication. Land was not held as a favor from the king; title was allodial. A man’s home truly was his castle.

This is so bad it's basically a total lie. Let's start with how he does not discern between free, landholding men, minor nobility and great aristocrats, three classes of men who would have absolutely no problem realizing that their lives, political power and the law that actually was applied to them were very different from each other.

The vast majority of men living in the middle ages did NOT actually have a fortified private manor aka castle, but a hovel that was protected from violation by other people most probably by the local lord or gentry, who as it happens was the biggest danger to your freedom as well as the judge over what rights you had.

>It seems, instead of the pinnacle of governance and protection of liberty, the constitutional form represents a significant step back from the liberties afforded to even the lowliest members of early mediaeval society.

That's not a point, that's straight up pure fantasy. The lowliest member of mediaeval society, unfree people, had more rights than we do now the same way that chattel slaves in the American South had more freedom then than as black people today, shoulders brutally weighed down with responsibility for their own life instead of a simple pleasure of having a master take on that dastardly responsibility.

The author has cherry picked data points, badly misunderstood concepts used in those cherry picked points, and then wildly conflated vaguely related things to create a utopian version of his entirely unhistorical mediaeval heaven.

The author makes vague claims and provides no evidence for them. And the sources he does site are questionable at best and purposefully dishonest at worst. No where does the author say what freedoms people actually had or how we know they were followed and enforced. There is no first hand source for ANY of his claims except the Magna Carta, which undercuts his own, that is that the past had some glorious freedoms that were around and freely followed. From the Magna Carta

> THE City of London shall have all the old Liberties and Customs which it hath been used to have. Moreover We will and grant, that all other Cities, Boroughs, Towns, and the Barons of the Five Ports, and all other Ports, shall have all their Liberties and free Customs.

Just from a superficial reading this implies that "Liberties and Customs" were afforded to London but then revoked and now formally reapplied.

The Magna Carta, and other historical documents like the Assize of Clarendon, are important because they formalized unwritten codes into laws, expanded rights, and set up a legal system that allows for non violent means of dealing with conflict. Without them we wouldn't have things like Habeas Corpus and instead be defending against arbitrary decision making by people like kings