NT "Personalities"
In this case, "personalities" does not refer to the plethora of Linux distributions, but instead to the NT kernel API interfaces.
NT was originally written as a foreign kernel (reimplementing VMS in C), meant to assume Win16/32, OS/2, and POSIX "personalities."
'Broad software compatibility was initially achieved with support for several API "personalities", including Windows API, POSIX, and OS/2 APIs – the latter two were phased out starting with Windows XP. Partial MS-DOS and Windows 16-bit compatibility is achieved on IA-32 via an integrated DOS Virtual Machine – although this feature is not available on other architectures.'
https://en.wikipedia.org/wiki/Windows_NT
I understand that PostgreSQL will run better under Linux emulation because fork() is faster than the native Windows equivalent. I wonder how that was implemented under the "LXSS" service mentioned in the parent article, as opposed to directly interfacing with the NT kernel as the POSIX system did.
Assuming a stable system call interface, (modern) NT is able to run many Linux distributions. My Windows 10 PC at work tells me that the following are available:
C:\>wsl.exe -l -o
The following is a list of valid distributions that can be installed.
The default distribution is denoted by '*'.
Install using 'wsl --install -d <Distro>'.
NAME FRIENDLY NAME
* Ubuntu Ubuntu
Debian Debian GNU/Linux
kali-linux Kali Linux Rolling
Ubuntu-18.04 Ubuntu 18.04 LTS
Ubuntu-20.04 Ubuntu 20.04 LTS
Ubuntu-22.04 Ubuntu 22.04 LTS
OracleLinux_7_9 Oracle Linux 7.9
OracleLinux_8_7 Oracle Linux 8.7
OracleLinux_9_1 Oracle Linux 9.1
openSUSE-Leap-15.5 openSUSE Leap 15.5
SUSE-Linux-Enterprise-Server-15-SP4 SUSE Linux Enterprise Server 15 SP4
SUSE-Linux-Enterprise-15-SP5 SUSE Linux Enterprise 15 SP5
openSUSE-Tumbleweed openSUSE Tumbleweed