My point is simply this: maybe the author wanted to write an OS that he could use on his PC without rewriting all of his programs.
Maybe he did not want to do OS interface research.
Maybe he did not want to do OS interface research.
Writing a research OS in D/Rust seems to me like someone claiming (before Tesla/LEAF were released) "electric motors are better for cars! Electric cars are superior to gas-powered cars!", but then instead of making an electric car that's actually comparable to a gas-powered car, they build an electric tricycle (velomobile) out of mostly bicycle components that weighs 40 pounds and seats one person and has a custom carbon-fiber fairing and a max speed of 30mph. Yeah, it's nice that you can build that, but it doesn't prove the assertion at all, because the vehicles are totally dissimilar and incomparable.