I see (in this article — no time to search others) you may have neglected the DoD support for edtech. I feel that, as with internet, there needs to be some big customer to power the sector forward. Sadly if my history serves me correctly this took umpteen years.
A bigger issue is that the market is too confusing to mere mortals (pace your efforts), especially higher ups. I worked in an organisation that imposed Blackboard with inadequate resources and we did our best but we ended up spending all our time on inappropriate initiatives that were never justified or ever placed in some road map.
Finally, on a plus note, I suspect that there is a major opportunity for someone with a clean slate to really succeed in this whole area. LMS´s seem to be on the way out with flashy (but similar appearance) front ends showing the way forward. As per usual the market will decide and my bet is that its the Health sector with compliance requirements where the smart money might be.