At this point, most people likely associated the word "phone" with something closer to a modern smartphone than a landline. Language can change. From my point of view, the problem is more that Apple set a precedent of these restrictions due to them being the first mover, and few mainstream phone companies have tried to break out of this idea (even though other phones are technically more flexible if you try hard enough).
I agree it can be pretty easy to set up a basic version of this, but eliminating edge cases, optimizing, and unit testing can make it take significantly longer.
Thanks for your interest! Currently, Microdiff does not have a patching functionality by default, and the API is different. If there is enough interest, though, I might make a compatibility layer to ease the differences, and it probably would not be hard to do yourself too.
This was not surprising, as many people already knew sleep helps your brain remember things. However, it is good data to back this up for people skeptical of the benefits and the "cutoff" time was interesting.