Agreed. I do think there is plenty of real-world application for Essence. I have some professional experience in this space (forth, embedded SBCs, micros) and a number of times designs got rejected on production costs because of the need to have hardware specified to the needs of the OS/GUI and not the small control program running in tens of KB of memory.

On first glance, Essence looks like it makes efficient use of hardware resources and, as you say, an ARM port makes sense. I can visualise an OS version of web packer type tools where you rollup your app/gui and just enough OS to run them on the target. I can say that people who I've worked for would pay good money for that sort of kit. Not suggesting closed source, but in terms of the usual caveat to management - paid support, open source longevity etc.