Like when graphics stack and drivers were "imported" into the WinNT kernel as an optimization for the user-space version. And thus began 30 years of "another week, another graphics subsystem crash/vuln".
Indeed. These are gigantic mistakes. The quest for performance is diametrically opposed to having a secure system. There will always be a price, sometimes a big one for having a system that enforces proper boundaries. In my opinion: if something can be a process then it should be a process.
Plan9 or HURD? Mach anyone?
I would not be surprised at all if we end up with radically different OS architectures than the 1970's model we have today.
I would. Things tend to congregate into an ossified mess over time. Case in point: our current model is from the 1970s.
But it works, and it is unclear if alternative architectures are viable in practice.
If the new model is incompatible with the old, no one will invest in it. It's like you show people a warp drive and they just stare at you not understanding any of it because all they want is a better car.
The boat long ago sailed on Mach/Hurd; there are probably better options in microkernel-land. There's Zircon, but Google laid off a bunch of the Fuchsia folks and has been pretty quite lately. QNX is still a thing, but closed source yadda yadda. Best hope there is probably the L4 family (seL4, et. al).