He has learned how to play most of the major musical instruments, typically well.
His vocal range once spanned over four octaves, he is sometimes considered the greatest bass player in the history of rock and roll,
About people who play multiple instruments. Lots of guitar/mandolin/banjo etc peeps. Drummers and pianists. People who cover that whole gamut as well – Macca.
But – string instruments (guitars etc not what is meant, violin/cello, upright bass etc), woodwind and brass. Very few indeed who cover across those three. And also, very few who cover those “major” ones and also one or more of these.
OK, Van the Man and saxophone, Bowie tried for a bit but not very well. Chris Rea is actually a good brass player – got the range and tone. But Rea is the exception.
So, why? One argument is that the minor instruments are just that, minor. So, why bother to learn one as a secondary or tertiary instrument?
Another – and this is rather groping for an argument – is the technical barrier to being good at any of them. You can make a fun noise out of certain instruments with very little technique. Punk bands showed that. But it is actually true. I’ve not played a guitar – never was any good – in 30 years but I could be giving you a perfectly servicable (shite, but servicable) blues bass line within a day of picking one up. Could gig within a month, maybe a week even. Sure, take me forever to be John McVie and the universe doesn’t have enough time left for me to practice up to James Jameson – but that last is true of everyone of course.
Fretless string instruments and brass – I assume reed wind as well but don’t know – take weeks of fiddling to get a sound out of them, or to be in tune. It takes months and months to be able to do anything you’d let out of the basement.
So, back to the beginning. Yes, of course musical talent exists. But so do barriers to using specific instruments. One barrier is that talent. But with certain instruments there’s a high technical barrier to get over before you can even think about actually applying musical ability. Given that incentives matter those with that proven musical ability don’t bother to pick up those instruments that have the technical barrier, not as second, fourth and tenth instruments they don’t.