And containers really are a VM-light, so you might as well use the real thing, in fact, VMWare for a long time thought that their images would be a container like thing and many larger installations used them as such.
On the other hand, I don't think the comparison between jails and docker is fair. What made Docker popular is the reusability of the containers, certainty not the sandboxing which in the early days was very leaky.
Inability to find a service I want to run on Github and 95+% of the time to be able to configure it and have it running and fully managed with usually just a one-liner shell script like 10 minutes later just by finding an existing docker image is the thing I’d lose with jails. That’s all of the value of docker to me personally. Jails could be a building block toward that, but last I checked there’s no deep and up-to-date library of “packages” I can reach for, using jails, which makes it pretty much useless to me.
1: I have like eight or nine services running on my home Debian system, they all auto-restart and come back up on reboot, and I’ve not had to touch Systemd once on that machine.
Well, what style difference exactly? GNU utils tend to be more verbose. Other than that, what is the difference in style?
It might be of homogeneity, i.e. the FreeBSD tools behave in a consistent way, while there are significant differences between the Linux tools, depending on which were the opinions of their particular authors about how the traditional UNIX tools should be changed.
For instance, at some point in time, long ago, in Linux the traditional "ifconfig" and a few related commands have been replaced by "ip", for managing networking.
The Linux "ifconfig" needed an upgrade, as it could do only a small fraction of what the FreeBSD "ifconfig" could do. Nevertheless, until today, decades later, I have been unable to stop hating the Linux "ip".
I cannot say why, because in other cases when some command-line or GUI utility that I had used for many years was replaced by an alternative I instantly recognized that the new UI was better and I never wanted to use the old UI again.
So while both FreeBSD and Linux have started with the same traditional UNIX utilities, they have evolved divergently and now they frequently feel quite differently, in the sense that the various options in commands or in configuration files may match your expectations only when taking into account the identity of the OS. Overall FreeBSD has been more conservative, but there are also cases when it has made bigger changes, but such changes seem more carefully planned and less haphazard than in the Linux world.