They’ve been in business for a couple of years already so they have their stable niche, but yeah the target audience for these devices is rather small.
IIRC they sell a couple hundred thousand phones a year which is a very small operation compared to big makers that can move that volume on a single model within their lineups of dozens of yearly releases.
These security measures don't actually deter the theft itself. The opportunity cost is simply too big, even if only one in 5 people are intimidated enough by the threats to unlock their phone, that still makes it worthwhile to steal iPhones.