There are a lot of things that get much, much easier from an accessibility standpoint if someone can operate a device by voice, instead of having to maneuver next to a switch, panel, or button.
Getting next to the button can be much more difficult if it means getting into a wheelchair, fitting your prosthetic, or having to find help because it's positioned too high or in an area that's too narrow.
Additionally, you can say a single phrase and turn off all lights in your dwelling, regardless of room. Minor win for able-bodied folks who might take only a minute or two to walk the house, big win for someone less capable.
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I'm technically capable enough to have removed Amazon/Google anyways with HomeAssistant in combination with WIS (https://github.com/toverainc/willow-inference-server) and Willow autocorrect (https://github.com/toverainc/willow-autocorrect).
Which gets me most of the things I cared about from an Echo without ever having anything leave my LAN. But it's a real PITA the setup.
There is basically zero middleground in this industry between "Amazon/Google have a permanent microphone that listens to everything you do" and "You have to manually flash ESP32s and configure servers".