Technology

It's demographics. Linux contributors & maintainers skew heavily to the older end of the spectrum (and, although not relevant to this point, also skew heavily male).

People who can contribute time to a project for free tend to be older because they are financially and career settled by the time they hit 50s. Raising a family tends not to leave a lot of spare time.

WiMax gang rise up

The article isn't entirely clear. I get the impression that the person in question may have been the sole maintainer for some hardware-agnostic parts of the wireless stack (which I'd expect to only need active development when a new standard gets greenlighted; should be bugfixes the rest of the time), co-maintainer of the drivers for some atheros chipsets, and the general oversight/coordination guy, but there are other developers working on specific drivers.

Obligatory XKCD: https://xkcd.com/2347/

Well, "maintainer" is usually a single person job. They didn't write all the code or whatever, just were the gatekeeper to what got added and making sure shit works.

So I mean, it's not great nobody is stepping up, but it's also not like they magiced up the entirety of linux's wifi support single handed, either.

That explains many things

Ethernet is a layer 2 protocol. It can run on many different mediums and cable types.