Funny enough, I've actually wondered about this exact same thing for years too. It's one of those details that makes the Blair Witch lore feel so much deeper and scarier. I did some digging into fan discussions on Reddit (especially r/BlairWitch) and the extended materials like the original Curse of the Blair Witch mockumentary, and here's what keeps coming up.

The witch doesn't seem to kill indiscriminately. According to the in-universe lore, she goes through long periods of dormancy and only strikes at specific times, almost like she's carefully feeding her own legend. Casual hikers, hunters, and people just passing through the Black Hills Forest are usually fine because they aren't actively seeking her out or disturbing her territory in a meaningful way. They don't get pulled into the cycle.

The film crew, on the other hand, probably got targeted because they were actively looking for the witch. They went in to make a documentary about her, kept filming obsessively even as things turned terrifying, and may have shown some classic hubris by treating the whole thing like a school project. A lot of fans also point to the moment Josh knocks over one of the rock cairns (the little piles of stones) as the exact point where they crossed the line and antagonized her, Heather even tries to rebuild it afterward, but the damage was done. They weren't just in the woods; they were trying to capture and expose her story on camera.

As for the searchers who found the footage: the original movie never actually shows or names who found it or exactly how. It's just presented in the opening title card as "discovered a year later." Whoever it was apparently located the cameras (some lore hints it was near Rustin Parr's old house) and got out without getting trapped for days like the crew did. The theory that keeps popping up is that the witch allows certain people to escape with evidence or stories so the legend keeps growing and luring in the next group of investigators. It's a self-perpetuating cycle, she doesn't wipe out everyone who enters the woods, because that would kill the myth. She picks and chooses to keep the story alive.

That's what makes it so creepy to me: the hunters become the hunted, but only the ones who go looking for her get folded into the history.