I worked in edtech for 3 years (left job last November). Spoke to many others at events (ISTE, etc). The main struggle was how to move content from one platform to another. Every product had its own proprietary format and most didnt have a way to export. I worked on a solution with a publisher but abandoned the idea the moment they mentioned not wanting to do an open format.
I also had some issues with student data being different across all SIS. Had to implement my own solution to normalize the data and serve it to my own production systems (eventually was sold to clients). This was never truly solved because the moment I left the company focused on another product (it wasnt a "data" company like Clever).