I'm sure he did. It is mentioned in TFA.

The author mentions this in the second paragraph...

He did:

"The mobile linux space isn't exactly looking good right now, but it holds some promise. Ubuntu Touch managed to survive being abandoned by Canonical, and postmarket is still seeing good development even if not having great hardware adapation at the moment."

Number of devices fully supported: 0

Oh, you linked to Fairphone 4, let's see:

- battery: partial

- audio: partial

- camera: partial

- fingerprint: broken

postmarketOS device support is a joke, they couldn't even get ONE vendor to support the OS..