Of course they're entitled to their opinions. Yet they annoy me because they tend to be the nit-picky types who fancy themselves to be clever although they are mostly just obnoxious. And, you know, I may not get paid for this and I may not have thousands of subscribers but I am still going to rebut their argument, gosh darn it. This will be short as it's a stupid debate to begin with and thus does not require much thought:
Firstly, people rarely sing the National Anthem. They tend to shout it. Go to any sporting event and you will see this is true. The people who have to actually sing the anthem are people who are supposed to be good at singing already; thus, the difficulty of the song -- which isn't even that difficult, if you don't add on all the annoying bells and whistles, which everyone does but nobody should -- should not pose a problem. Secondly, the American public generally does not have a problem with the anthem. I admit that I feel a swell of patriotic pride whenever I hear it played, especially when I'm with a large group of fellow Americans (or, really, anybody who likes the USA enough to stand around and listen to the anthem), and I suspect that most of my fellow citizens feel the same way. Also, like, good luck trying to change it -- you're definitely, absolutely going to get shot down as a devil-worshiping America-hating fascist. (Don't worry that the insult doesn't make sense. People just like to get angry.) Thirdly, maybe it's not the best song ever written, but it's a hell of a lot better than many of the state anthems. Take Maryland for example, whose state anthem is essentially a southern-sympathizing, anti-north, pro-slavery Civil War relic. It's not so much the fact that it was made the state song that's the problem... it's that it was made the state song in 1939. And nobody has changed it since then -- in fact, there's opposition to altering the lyrics on the basis of 'preserving state history.' Right, because the state song -- which nobody even knows, may I point out -- is the most important place to preserve the racist history of a state that never even joined the Confederacy. Oh, Maryland.
(I feel sometimes that I come across as super pro-American on this blog, which isn't really true in my general life. This is mostly because whilst I normally freely admit the many flaws in the workings of my home country, I still feel quite an affinity for it, and the annoyance at hearing people going on and on and on about how terrible the USA as if all other countries are perfect builds up over time and eventually provokes me to the point where I am driven to post a rant about it over here. Lucky you!)
P.s. I'm not well versed in the national anthems of other countries, but I must admit that I love "God Save the Queen" (or King) despite the fact that I'm quite indifferent towards the British monarchy. I quite like the Canadian anthem as well. Let song unite us all, etc. etc.