I don't get what's firing up these anti-monarchy people. I don't give a shit about the King or the royal family or anything but they wield absolutely no power, it's a huge part of our culture and history, they bring money into the country, and many people love it. All they do is turn up at events and try to stop people enjoying themselves. There's far more important things to be complaining about.
That being said, I think he should have been allowed not to say that part, simply because it doesn't matter.
Firstly, I reckon it’s debatable whether having an active monarchy is a net gain financially (how much could we charge for admission to Buckingham Palace?).
But, for me at least, it's simply a matter of principle. I believe we are all born equal, and that nobody should be given special treatment due to something as trivial as their ancestry. Having a monarchy flies directly in the face of many values I think we as a nation value deeply.
Also they have a lot of land that their great great ... Grandad nicked from the Saxons and I wouldn't mind that being nationalised.
I would say it does matter as he's going to be a legislator in a constitutional monarchy. In that world the crown is the people and the people are the crown. To refuse to defer to the crown is to refuse to serve the country.
It's why Sinn Fein refuse to say the oath and take their seats, and I can respect that, but that's your choice. You don't get to pick and choose bits of the oath.