It takes quite some research to find single-purpose devices, that are tailored for a specific use case - and are not overburdened with often unused features. There‘s not enough metadata out there on ecommerce sites to filter for that.
Take the microwave example:
I‘m happy with the Samsung MWF300G microwave which does just one thing (heating stuff) really well in a very straightforward way:
One haptic dial for duration. One for Watt. And a simple display for time.
Just use the duration dial to set the time. That‘s it. You‘re done by turning your hand just once.
It starts automatically. No start button needed. No program selection. No stop button - just dial it back to zero if needed.
A neurologist prescribed me Metagelan.