Hi @Raposa, I am not deeply involved in Lomiri, just with Mir and it's ecosystem. So I will answer those questions I can.
This could be useful background on the Wayland ecosystem:
https://mir-server.io/docs/ok-so-what-is-this-wayland-thing-anyway
is lomiri available for distributions other than ubuntu touch, or architectures other than arm? if not, would significant effort be needed to port lomiri to other distributions or architectures?
Yes, it is, for example, in the Ubuntu 24.04 and Fedora 40 archives and available for multiple architectures.
https://packages.ubuntu.com/noble/lomiri
is lomiri using wayland? is lomiri a wayland compatible desktop, capable of running wayland and xwayland applications seamlessly, what is the relationship of mir to wayland, and what is the architectural relationship of mir to lomiri?
Mir is a library for writing Wayland compositors and enables using Xwayland to support X applications.
https://mir-server.io/docs/developing-a-wayland-compositor-using-mir
Lomiri is one of multiple Wayland compositors written using Mir, and supports X applications. (Indeed the Mir support for X was initially contributed by one of the Lomiri developers.)