And indeed it is really about the minimalisation of workload and longlivety of the project.
We want to keep EndeavourOS running and not depending on personal likings or complex setups/changes, it have to stay easy to maintain for development and the user, now and in the future and to be sure we will be rolling into the future, we need to decide the best way to make that sure.
And for the Desktop on the ISO it is not XFCE4 or LXQT, nor most of the others the best consens is KDE.
But this does not say that you can not install XFCE4 anymore, it is still there same as GNOME and others.
It is only about the LiveSession that holds the environment for the installer, XFCE4 was never the default EndeavourOS Desktop also we had it setup appealing to many users (this was not the plan).
We choose it because in that time it was stable and had was very slow in progress and changes upstream, plus it was a good choice for the Live Environment compared to the other two kde and GNOME with endless issues running the in a live environment in that time (2019) this has changed completely… today you can use almost all Desktops on a LiveISO… aside from issues using wayland (still…)
And we are still in early development for this, the change has to prove itself first and we are running a thorough test period to see how this environment performs in all possible environments.
If it turns out to be problematic, we will not pursue the change.