In reality, these providers have simply leveraged AWS or a similar offering. Their UI's are much more refined than FreeEED right now, but ultimately, there should be no reason that FreeEED cannot catch up and surpass them. Arming companies and smaller law firms with sophisticated and virtually free eDiscovery processing software will have a tremendous impact on the way litigation is conducted.
Undoubtedly, companies like Logickull and Everlaw are playing a very important role right now, and they deserve to make money for their efforts. With that said, the platforms they offer are ultimately not accomplishing any technological feats that the current myriad of free webmail providers are not already accomplishing. I believe that if more developers understood that there is a dearth in available of tools for email review -- which really just requires easy tagging -- this whole space could be dramatically improved.