Are singers musicians?

There are musicians, and some are professional, others amateur. Some musicians are great musicians, others are merely good, and then there are bad, very bad, and awful . . .

Maybe there's a spot in there for Yoko, and Johnny Rotten

I remember when the local authority (city hall) received a noise pollution complaint about Ms Ono's piano playing, I thought to myself at the time that I would not complain about her piano playing, but only when she started to sing,lol.

Johnny Rotten's voice is ok, I mean when he sang in his group P.I.L he fitted the songs well, and they were really good songs to!
Perhaps there is a spot for Bob Dylan, like after ...awful....

I am sure when a 'singer' needs to right on a form 'occupation', that do indeed (and quite correctly) put musician as their occupation as opposed to something like
throat warbler..............

Here's how I see it:

A singer that cannot play a musical instrument is a singer and not a musician. A person that can both play an instrument and sing is both a singer and a musician and if they can write music, they are a composer as well. The human voice is instrumental in singing, but it is not an instrument.

So then, technically speaking Johnny Rotten is a musician?

Absolutely.

Imagine trying to substitute Sting, Bob Marley, Jerry Garcia, Jim Morrison...or many others on a version of "God Save The Queen"

It just wouldn't be the same.

gotta go with the dictionary here...my dogs can sing, but they can't play guitars or keyboards. those lessons were a waste of money.