The Star-Spangled Banner is a song about a battle during the War of 1812 (not the Revolutionary War, as some think). It has a range of an octave and a half. Professional singers routinely struggle with it at sporting events. It was written as a poem in 1814 and set to the tune of a British drinking song. It became the official national anthem in 1931, which means it has been the official anthem for less time than it wasn't.
I propose a different song we all know. America the Beautiful is a song about America: its landscape, its ideals, its people. It is singable by a normal human being without vocal training. It was written by a woman. It has been proposed as a replacement anthem for over a century. Most Americans can hum it start to finish.
The only argument for keeping The Star-Spangled Banner is tradition. Tradition is a fine reason to do things. It is not a good reason to keep doing things badly.