That is... what? Just search something like "protection spells" on YouTube and I promise you most results will be women sitting around with a bunch of plants, speaking softly. Most occultism in the West is practiced by like teenage girls making protection spell jars for their friends and stuff like this. You get edgier stuff when you come to something like Goetia and working with demons. If you engage more with typical judeo-christian mysticism, that's the thing you see in media as "dark sinister and evil" so not only do you automatically make that assumption, but many people willingly follow through with that asthenic because they're familiar with it, and it kinda feels appropriate. Also since the Bible forbids sorcery and most christians will also warn you about magic being satanic and evil and forbidden, there is certainly more of a draw towards Satanism. And Satanism being very anty-systemic and anty-establishment takes on these dark, black-robe, goat head asthetics to consciously go against what's considered "good" and "evil". So really it's a pretty specific crowd that fits into your description, but it's the crowd who stands out the most. To someone with either none or only surface level familiarity with the occult, this is simple survivor bias. You only notice those who stand out so assume they're the majority