ly2en, #Podman has been ported to #FreeBSD. And it can run Arch Linux for me.
Linux containers in FreeBSD can start through the old good #Linuxulator - which does not support complex features like cgroups or namespaces, which means I probably can't run a container inside a container. Yet.
But this Linux layer is actively supported in FreeBSD for almost 20 years and is rock-solid! It started in 2006 at Google, based on Linux kernel 2.6 and today it shows up as 5.15-compatible!