It has a live physical instrument connotation to me as well.

There are people who play synthesisers live, whether on a keyboard with a pre-set patch, or a modular synthesizer making experimental sounds. I'd call them musicians with only a little hesitation. But if they do it offline and record it? Less sure.

Also, is Taylor Swift a musician?

> is Taylor Swift a musician

If only for her being a singer, I don't see how she _wouldn't_ be a musician