Yes, title is very misleading. For the curious here is the list of currently supported phones: https://wiki.postmarketos.org/wiki/Devices#Phones
You could write a similar article: How to install docker on your microwave oven: Step one, install a linux distro on your microwave…
Nonetheless PMOS is genial, I installed it on my Kobo ebook reader.
And you generate traffic for them, thanks. You could just directly link to the install docs on PostmarketOS, not for a shitty third party site: https://postmarketos.org/install/