There are two kinds of music fan – those who get excited by new genres and those who treat them with disdain. Back in the 90s the UK music press was notorious for its addiction to micro-scenes and flags of convenience – fraggle, new grave, collision pop. Some were absurd, some were successful, some were both. (When the internet came along, it was rather a shock to find that America had taken shoegazing seriously for years.)

Musicians themselves would often chafe at the suggestion that they were anything other than fearless trailblazers, but I was always on the genre-mongers' side. Not just because they made following music more entertaining, but because there's something fascinating about seeing different people work through the same basic idea. Being part of a movement – even an invented one – gave you a more interesting context to explore or break from.

I spent an afternoon this week listening to Salem's recent I Buried My Heart Inna Wounded Knee mixtape, an example of "witch house". My curiosity as a casual listener had been piqued by talk of something intriguingly queasy: slowed-down hip-hop beats, crude electronics, nerve-jangling samples and bad-dream sounds. I got exactly that – I also got a lesson in how genres work today.

Researching a new genre nowadays means following other people's breadcrumb trails of discovery: the first thing you realise is that you're always a latecomer. A search for witch house pulled up a Drowned in Sound forum thread from May, linking back to blog posts from February, then taking in new references across the summer. All these links, and the thread itself, brought me hours of music very quickly, and a sinking feeling that I was missing the point.

The problem is that idea of the "casual listener". On my brief quest for witch house, I'd also found plenty of sceptics. Some engaged with the music and scene, and their criticisms were fascinating. Others were less useful. They were simply genrephobes: always ready with a damning dismissal or the evergreen accusation "emperor's new clothes". Implicit in their criticism of new genres is a sense that the music couldn't stand up on its own without its supporting context. But this seems unfair if the music isn't trying to. Stripping music of context, after all, is what MP3 culture has been so good at – unbundling albums, making music of every culture and time available to be dropped willy-nilly onto an iPod playlist. It's been liberating, but a backlash is no surprise.

Artificial scarcity is one way of restoring context to music – releasing it on non-digital formats, or never recording certain tracks. In the case of witch house, the scene's penchant for non-Googleable names (oOoOO or Gr†ll Gr†ll) may be an attempt to create scarcity. But all it means is that pages about the scene as a whole end up higher in the rankings – witch house is still very findable.

Perhaps the strange names work as signposts, not barriers. Scarcity isn't the only way to revalue music, another is to present it as part of a total aesthetic, free but immersive. Witch house comes across as a curatorial genre – the syrupy, drained and hacked-apart music only as important as the night-time photography, the treated found videos, the ritualised typography. Insisting on separating the music from everything else is like judging a gallery installation from the brochure photographs.

That is why witch house isn't for the casual listener – not because it's hard to find, or expensive, or particularly "difficult", but because it requires a certain sacrifice of reserve, maybe even of dignity: you buy into it whole or not at all. In that sense it fits its horror trappings perfectly – a ghost story requires exactly the same willingness to be affected. You might still come away thinking it's rubbish – aesthetics can be poorly realised or fundamentally flawed, after all (and ghost stories not scary). But what witch house tells me is that genres now aren't exercises in innovation or marketing, so much as ways of framing an experience. And if you won't feel open to that experience, your investigation of it won't get far.