Can I answer that one? I’m sure Grany will come along later and give her view.
In the highly unlikely event that Johnson would want to stand for a role that would have no political power, and a majority of the population want him to be President, why would we have to safeguard ourselves against that? What would be so dire that we had better stick with the medieval model instead?
So Johnson gets elected President. He turns up at official events and gets to shake hands with powerful people. He gets to feel important. He visits Heads of State in other countries. How would we notice the difference from what he does now? He has to abide by an (as yet unwritten) constitution that says his power is mostly in making sure that the constitution is followed. The real power in the country stays with the PM and Parliament – as it has been for decades, maybe centuries.
And if we think President Johnson isn’t very good at the job, we don’t vote for him next time. Whereas right now, if we don’t think the Head of State is very good at the job, tough luck, we’re stuck with him till his son takes over. And we won’t have to support President Johnson’s extended family in their multitude of fancy houses and he doesn’t get to have his own laws about inheritance or tax. Unlike what we have now.
What on earth do we have to “safeguard” ourselves from??