In contrast to the Linux operating system, Freebsd is a less known software which should be introduced. The most important period was until the year 1990 in which BSD Unix was the defacto standard for Unix systems. During the 1980s, Linux wasn't invented yet and very advanced projects like the Sun has emerged. Unfortunately, the period since 1990 is less successful for the BSD operating system. First problem was that BSD was splitted into different sub projects like Freebsd, netbsd, openbsd and dragonfly bsd. Second problem was that since the year 1995 the University Berkeley stopped the development of code. So the BSD project has become a non academic project.
FreeBSD itself is running well so it is too early to describe it as a dead end, but many projects closely related to FreeBSD has become obsolete. The mentioned company SUN which was famous for Workstations and the Java technology has stopped its operation in 2010. The OpenSolaris operating system which is working with ZFS and dtrace was canceled in 2009. Another interrupted side projects are PC-BSD (canceled in 2018) and perhaps netbsd which has a very low amount of commits in the last year.
Let us take a closer look at FreeBSD itself. It the largest of the remaining BSD projects and has around 11000 commits per year. In comparison, the Linux kernel has around 74k commits per year. The user experience for FreeBSD on the desktop is disappointing. Most wlan cards are not supported, and the drivers for sound cards are poorly maintained. The user share who are prefering FreeBSD over Linux on the desktop is likely very low. Second problem with the FreeBSD ecosystem is that because of historical reasons the code isn't available under a GPL license which stands in contrast to other large Open source projects like Gimp or the Gnu c compiler.