It's called VM-like because:

- Often boots user land like a VM (i.e. PID 1 is not the process you want to run, but whatever metal or VM freebsd runs as PID 1)

- Normally has its own network stack (VIMAGE)

- Normally runs a bunch of background services like a regular VM or on-metal would.

- Normally has the entire copy of user-land

- I've never seen short-lived jails either - you make a base dataset, clone it, but after that, you just run `freebsd-update` like you would in VM.

The majority of jail users treat them like lightweight VMs, only difference between VM and Jail from consumer standpoint: shared kernel, access to a subset of host's FS (sharing host FS to VMs in freebsd is not as easy as it is on linux).

To be clear, it's possible to use Jails like Docker, there is just no good tooling to do it. People would yell that whatever we have for jails is all we need with foam from their mouths every time you mention it.