(I think Dave was being ironic with that Barbershop comment - Dave?)

I'm going to play devil's advocate for a moment. The issue isn't always simply a matter of taste. Sometimes, someone is so offended by a particular artist or recording that they can't stand to hear them praised. And sometimes there may be some basis for their attitude. For instance, if someone comes on gleefully praising some band for their infectious melodies, pleasing harmonies, etc., but you have been horrified by this band's hate-filled lyrics, you may feel compelled to respond, rather than to just say, oh well, it's all relative ...

Also, there are people here with strong opinions about what constitutes a worthy approach to a particular type of music, and what may threaten that approach - for instance, let's say you see the young inheritors of some long tradition collectively turning their back on it, taking on some completely different tradition, then marketing it as the tradition they have in fact rejected - well, you might be inclined to react to praise for the young'uns doing such a fine job of preserving the old tradition.

On the other hand, there are a lot of people who couldn't care less about any of that sort of thing, and can't understand why anyone else would, and ascribe any of their griping to pure bloody-mindedness. Their take on the last example is, it's so wonderful to see these young people throwing themselves into music instead of organized crime that no one has any right to criticize what they are doing.

We're talking about different personality types. Some simply 'enjoy the music or don't enjoy it', and can't understand why anyone would judge it, or pontificate about it. Others can't understand how anyone could enjoy or not enjoy music without thinking seriously about why they respond as they do to it ...

Having said all that - there are those who apparently like to insult others at any opportunity - and the internet provides no end of such opportunities. Nothing to do with music at all, really ...