No, it's not about users picking a camp, it's about developers.

It's been a long, long time since I've seen an application utterly fail to load because it's a GTK/QT/etc framework running under a totally different DE.

Gnome apps look ugly as hell under KDE[0], but they still work. As a user, you don't need to know or care in any way. It'll run on your machine.

[0]I don't know if they're ugly because of incompatibility or if that's just How Gnome Is. I suspect the latter