I’ve hired plenty. They were sometimes the best engineers at my company, specifically at executing tasks that were very difficult but they were experts at, and others would have had to take time to spin up and learn the art.
The drawback was that they were pretty much only interested in that specialty. They might be curious about other things, but they were genuinely happiest doing what they loved.
Reminds me of that joke story about a needle-point sharpener guy who's better than anyone else in the world at it, but then surprised when he accidentally learns about the needle eyes. After all, the needle eyes are not his specialty, he's not required to know about them!
The drawback was that they were pretty much only interested in that specialty. They might be curious about other things, but they were genuinely happiest doing what they loved.