I promised to take up the advantages of the standard banjo over the capo-ble banjo. They are important, but not for everybody.
The main advantage is that the standard banjo has three more frets. That’s not my whim; breaking strength rules the length of steel strings. A string longer than 22 inches will break if you tune it up to 5th string G. The shorter 5th string on a standard banjo makes the longer 1-4 strings possible. On a capo-ble banjo all the strings are the same length, constraining the length of the neck.
Those extra frets on a standard banjo mean a lot to the most accomplished banjoists; they venture high up the fingerboard all the time. If you, like me, are not one of those stars, you probably don’t care about those missing frets. The highest I go on the fingerboard is the 14th fret in Janet Davis’s wonderful arrangement of “Chopsticks,” in Famous Banjo Pickin’ Tunes.
Those shorter strings 1-4 and the slightly longer 5th string have to affect the tone of the banjo. I really don’t know what that affect is, though, because the only capo-ble banjos I’ve ever heard are my homemade ones. I think the difference would be small, but I can’t make a fair comparison.