You would still need hardware to communicate over the various smart home standards(433,bt,ir,zigbee,wifi,etc)

And that hardware doesn't need to communicate with the cloud, see things like this zwave usb stick (which works GREAT for zwave with home assistant and a raspberry pi): https://aeotec.com/z-wave-usb-stick

I agree! I personally have a z-wave stick, hue bridge, lutron bridge, a custom IR transceiver, etc automated w/ hass. But I can see the temptation to buy a one-size-fits-all device which can communicate with all those products(or at least their other hubs).