App uniformity... The history behind that is that @bnvk used to lead for Qubes usability. Generally to improve usability, once has to reduce the mental load for the user. Makes sense. His view was, that users who used the Fedora template who learned how to use applications there, be it NetworkManager or kate text editor, would benefit if they must switch to a Debian template for some reason, if they were presented with the same default applications.
("Just install it." doesn't cut it from usability view. Mental load. Knowing the names of applications used beforehand, how to install them with Qubes difficult installation in TemplateVM and required AppVM reboot...)
The same reasoning then would apply for switching around Debian, Fedora and Whonix templates. I am pretty sure that lead to https://github.com/QubesOS/qubes-issues/issues/1781 being created. Now, since that does not seem like a Qubes goal anymore, no need to port Whonix from KDEish to GNOMEish applications just for app uniformness sake.
Similarity to between Non-Qubes-Whonix and Qubes-Whonix, similar package dependencies (includes app uniformity between Non-Qubes-Whonix and Qubes-Whonix) makes it a lot simpler for me to maintain both, Non-Qubes-Whonix and Qubes-Whonix. Any fix/change on the one will likely work for the other also.