It's weird watching the Linux development community go from the position that Windows apps tightly coupling to Windows was bad because it made those programs more of a pain to run under Linux (most of the time requiring Wine) to deciding that sticking with cross-UNIX platforms was just no longer worth their time because Linux "won" the UNIX wars.
DBus (the software, rather than the protocol) isn't required on Linux anymore than it is on OpenBSD. It's required by the Plasma and GNOME desktop environments, most KDE and GNOME applications, and any other desktop environments or applications that want to use it.
It's also cross-platform, and runs natively on OpenBSD, NetBSD, and FreeBSD. It does not leverage a compatibility layer, and depending on it is in no way comparable to requiring an emulation layer like WINE.
Don't compare Linux and Windows, thats in bad faith. Developers just want to accomplish the best software they can, its all done in the open, but that doesn't mean they have to design software for other systems with different capabilities.
