The thing about smart home hubs is that you actually need one. Zigbee or z-wave or some other 900MHz channel is a really good way for these smart home devices to talk to each other, and for that to happen you need some sort of radio operating as a 900MHz hub.

It's not just that all these vendors want to be the hub, something has to do the communication.

I'd say that recent developments in long-range low-power radio networks (like LoRa, but see the list at https://en.wikipedia.org/wiki/LPWAN) might change this.

Of course it still makes sense to many here to run their own gateway for reasons of privacy and control, but perhaps the market at large could go for city-wide third-party networks, or something. Of course not everyone lives in cities, but perhaps shared networks might work in more rural settings, too.

I have no idea. Those are very different concepts and approaches (closed vs open source).

Apple wanted to use the desktop computer as the "hub" to sync your various electronic media devices.

This "hub" is for IoT devices.

Seems pretty different to me too.

iTunes was "getting nowhere"?

Largest market cap in the world is nowhere now I guess.

And would it have reached that if it was chained to the Macintosh dongle? How much of that activity comes from it being available on Windows?

Jobs hub was not iTunes, it was the Macintosh sitting in the livingroom corner.