Google's Fuchsia is still the best bet for a genuinely new OS that may at least find a niche. Capability-based microkernels have been exciting research project

Google's Fuchsia is still the best bet for a genuinely new OS that may at least find a niche. Capability-based microkernels have been exciting research projects for decades, and Google has apparently made one that achieves acceptable performance, which was a significant challenge.