Moreover, many laptops working on Linux perfectly, are not Ubuntu certified. Lenovo Legion series generally works well, but it is not in the Ubuntu list. Id we'd make a list of all 8/10 or more compatible laptops, it would be huge.

> More sensible, IMHO, might be to bolt the FreeBSD user space unto the Linux kernel.

A lot of BSD utilities that are not POSIX has really close interaction with the kernel. OpenBSD’s *ctl binaries are often the user-facing part of some OS subsystem. Linux subsystem often expose a very complex internal that you need to use some other project to tame down

IMHO the biggest advantage that Debian/kFreeBSD would have had would be first-class ZFS support. You can use ZFS with Debian today, but the license problem means it only gets supported through DKMS, which is a pain; a FreeBSD-based Debian could ship binary packages for ZFS that just worked out of the box.

> More sensible, IMHO, might be to bolt the FreeBSD user space unto the Linux kernel.

Chimera Linux is doing something like this, although without aiming for the full BSD experience, just utilising its core userland [1]. The project is in an alpha stage.

1: https://chimera-linux.org/about#alternative-userland