Nigel, it's not about the performers or the performances; it's about the tonal characteristics of the instruments themselves. I don't think I'm alone in this. If you favor certain genre's of music to which that instrument is totally foreign, there's a good chance you're not going to be a fan of that instrument. In some cases it's genre association; for instance, Ukuleles ate typically associated with Hawaiian music. Having lived in Hawaii, I can honestly say that I truly dislike Hawaiian music. Harmonicas remind me of 'Mississippi Delta-type blues', about the only blues form that I dislike. Clarinets = Dixieland, one of the few forms of jazz that I dislike. Accordions....most of the (sometimes self-deprecating) humor involving accordions, comes from accordion players themselves.
I think everybody has things, including musical instruments, that they don't like. The reasons vary; sometimes it's cultural bias, sometimes unfamiliarity, sometimes 'associations', and sometimes because they just don't like the sound of the thing. Many fans of classical or theatre organ think the 'Hammond' sound is a joke (it probably does the worst job of emulating a pipe organ) and can't understand why anyone would like it. Many Hammond lovers feel just the opposite. There's just no accounting for tastes.
The important thing is, there is no right or wrong here, and good or bad is usually a function of the performer, not the instrument. So live and let live....just keep that glockenspiel away from me