"Like any complex, real-world system, the reach sometimes exceeds the grasp; some parts of Genera do not fully implement the vision as we have expressed it. Genera contains some artifacts of its development history that are not exemplary of the design philosophy. We hope that the small failures of the philosophy will not distract you very much in your appreciation of the large successes."
The level of complexity of these systems is high even for today. But complexity has nothing to do with why we struggle today with vim, emacs, eclipse with gdb or what-have-you for developing and debugging.
Those who understand the system are few, and the time they have at their hands is scarce to begin even contemplating the amount of work required to develop a free alternative to genera.
I have no other explanation of why so many hobby projects started and failed at replicating what is still state of the art in programming environments.
