I think the underlying thinking behind most educational technology is take the work out of the hands of the local practitioner, deskill the teacher. While the sellers and developers of edtech will never admit this is the case and my not even realize it themselves it basically amounts to central planning.
If a computer program is going to teach a kid math the pedagogical approaches it takes will be more or less fixed and ones designed at some central facility somewhere. It wont be the paradigm the local instructor was using and it may or may not add to clarity.
I am in my early 30's depending on who you ask I am either the last of the gen X'ers or among the first of the so called millennials. Outside of some of the education television experiments tried in classrooms on boomers, I saw most of the early experiments in edtech. I had a number of older teachers who had spend years drawing their own little cartoons, crafting their own little narratives to help us understand. I also had younger ones who wanted to try out all the new MECC stuff. I was in Minnesota. If that worked for you great, if not the instructors were mostly caught flat footed with no alternative ideas about how to convey the lesson, unlike the other teachers that had taken the time to develop their own materials.
Central planning isn't any better for education than it is for economies. When edtech stops trying to teach and really starts trying to make teachers more effective it might work. A better hammer will allow a good carpenter to get his framing done faster and possibly even done better. A better hammer isn't a robotic carpenter though, but most edtech attempts to be a robotic teacher.
My sister teaches Highschool math subjects. She loves Mathmatica. She says it lets throw up a visualization on the screen the really helps some of her students get it. Its faster and better than anything she could scribble on the whiteboards. She is using it though in the context of her own lessons to explain her own contrivances that show how to apply the math. Its a generic tool though, while lots of educators use it isn't designed only for education and it isn't designed to teach any specific lessons.
Edtech needs to focus on giving teachers quality general use tools and class room appropriate hardware on which to run them. It does not need to be trying to create a digital textbook equivalent or play instructor on its own.