One argument says that the monarchy still isn’t a constitutional irrelevance, and having a constitutional relevance accountable only to a revolution is dangerous. In a sense it’s true that they’re still constitutionally relevant because various notionally royal powers like being able to declare war without parliament’s agreement or being able to decide when lifers are released from prison are de facto wielded by ministers. We could change this without abolishing the monarchy, though. One also occasionally hears that the Queen would get some real power in the event of a constitutional crisis, but it seems to be a belief exclusive to people who write letters to the Telegraph and I’ve never seen any evidence for it.
Another argument is that the monarchy is a waste of money, what with all the money we pay them directly and the money we spend on moving them around and protecting them from Gavrilo Princip. Of course this seems like money down the toilet, but some people think that they make more than they cost because of their effect on tourism. It’d be a shame to abolish the monarchy to save money if it turned out to be a false economy. Perhaps some proper research should be done into it, instead of monarchists and republicans asserting what they would like to be true on the basis of no evidence at all.
The other problem with them is that they’re a nuisance and a national embarrassment, running around saying un-PC things, not taking their socks off in the Golden Temple and torpedoing any architectural projects that would look out of place on a chocolate box. They make us look like idiots, and there's nothing we can do about it. But people accept that sort of thing from their children, as I don't think I'm the first to point out. We let them have a go at doing various jobs, make foreign businessmen shake their hands and say 'hello Andrew, haven't you got big!'; we support them financially, we won’t shut up when one of them gets married, and when one dies they are mourned. Now I don’t feel at all paternal towards the royals and wish they’d go away, stop asking us for money and never darken our doors again. I don't care when they get born/married/killed any more than I care about these things happening to anyone else. They are, lest this sound callous, not my children. But a lot of people seem fond of them, and if enough people want some collective children then that’s what a democracy can be expected to provide.
Another argument says that there is a useful constitutional or at least ambassadorial role to be played by a proper head of state, and we’re missing out on this by only having a pretend one. I expect this is true. Other countries want to talk to our head of state whether she’s a proper one or not, so perhaps it should be someone we’ve elected and given some real power. (Perhaps there’s something to be said for according people respect in a non-arbitrary way.) And some countries’ heads of state do have real power, even if it’s only for resolving constitutional crises. What are the alternatives? Is everywhere with a proper head of state wasting their money? Or are we missing out? I don't see how we can both be right. So maybe there is a case for cutting the royals loose, in spite of my fellow countrymen’s unexplained fondness for them.