> BSD's ifconfig isn't really related to Linux's ifconfig anymore because BSD has continued development and the Linux fork or version (don't remember which it is anymore) hasn't.
There's a simple solution to the lack of maintenance on ifconfig: Maintain ifconfig.
It's open source. Feel free. I'd expect there are significant architectural differences between Linux and BSD by this point, though, that would make it quite a challenge. Alternately, it might be like adding major new features to Xorg: possible but extremely challenging.
My understanding is that the Linux version of net-tools was based on the BSD software, but I don't know how much code is actually shared between the two projects. It was intended to be syntactically equivalent and support the same features (at the time). You'd probably find it easier to write a net-tools-like wrapper for iproute2.
Yes, someone could have just extended net-tools. But nobody did. Instead, they wrote iwconfig and other tools when they were needed, and then someone decided to write a competing package, iproute2, that did everything. And that package added feature support when they were added them to the kernel, and bugs got fixed. Those didn't happen with net-tools unless each distro took care of it.
There's a simple solution to the lack of maintenance on ifconfig: Maintain ifconfig.
There's no need to break shit.