Well, I use FreeBSD on my personal laptop and work at a company which uses FreeBSD for its appliances. That’s true, FreeBSD’s market share is tiny in comparison to Linux, but it seems like there are still a number of companies looking for FreeBSD developers.
It’s also reassuring that even though FreeBSD ecosystem gets a lot less attention than Linux, it still enables companies like New York Internet to be one of the most reliable hosting companies out there (https://news.netcraft.com/archives/2020/12/02/most-reliable-...).
I focus on technologies which have seen a steady growth over the years, like FreeBSD. The benefit is that the knowledge you obtain tends to stay relevant for a long time.