This is an interesting mechanism, but is it really that difficult to boil rice for 20 minutes? I'm not exactly Gordon Ramsay, but I don't think I've ever failed to make decent rice.
Rice cookers can generally make a pretty large volume and they're still rather efficient at doing so. If you get the water and rice ratio to your liking it will make nearly perfect rice every time at the press of a button. The best ones have multiple markings for white and brown rice on the bowl so you don't even need a measuring cup to do this.
It has a little countdown timer so you can get your sides ready on time. It plays a little song when it's done. It covers and seals up well and can keep rice warm and good to eat for a few hours.
There are only two parts that you have to wash, the bowl itself and the detachable lid seal, and one you have to wipe down, the steam vent cap.
I generally don't like special purpose tools in my kitchen. The rice cooker has been a part of it for 20 years anyways. It's simply too useful without any additional hassle that it has easily earned it's place.
If you're eating a more western diet with rice only a handful of times a week, it's probably overkill as a single-tasker.
As for today? Well, too hot on the stove or a phone call comes in, and poof, there goes all the water and the rice burns. If you're making rice 3 times a day, it's easier and safer to cook in a machine that guarantees perfection every time.
Is it really that hard to grill bread? Nope, but you have to pay attention somewhat to stop it burning.
Once you hit a certain volume of usage, an automatic device makes a lot of sense.
Not really, you can make toast on the stove in about 1 minute, rice takes 20.
For rice nearly zero attention is necessary with the correct amount of water.
And in that 20 minutes you get enough rice to fill mutiple people up.