There's an attempt at heading off the driver commentary with a note at the bottom. The note makes some hand-wavy thing which is essentially "assuming you have an army of people with specifications, this won't be a problem", but that assumption is crazy. Fuchsia is a real OS effort funded by Google (at varying levels of funding through it's lifecycle, which is still ongoing AIUI) - I worked on Fuchsia for a number of years, from approximately the time the kernel had become usable, through to launching on nest hubs where it replaced the existing OS from bootloader to GUI. Drivers remain a huge problem for Fuchsia despite funding. SOC vendors don't provide docs or assistance, even for serious efforts, they demand money first - they're literally holding the software world hostage with this activity.

After leaving Fuchsia and reflecting on the whole thing, I really believe that despite the many problems Linux may have over the long term, the only viable strategies for a broadly and practically usable safer OSS system are either: someone donates at least $2bn to get it done in a PBC well managed and focused over a decade, or you slowly mutate Linux into that thing. Anything drastically different is, for now, dependent on the world being a different shape / people & companies having different attitudes than they do. I'd love to see something like Redox prove me wrong, but real world experience suggests that's extremely unlikely. RISCv is the one thing in flight that might "change the shape of the world" enough to alter this, but RISCv comes with it's own stack of long challenges to overcome to meet the originally stated goal of broadly and practically usable.

Writing a core kernel and usable userspace isn't something to be trivialized, but by cost and work volume, getting a broad set of drivers is far far more effort by an astronomical margin. The OSDev community has thousands of OSes to explore, and barely any drivers that do things a user actually cares about.