I could see just powering through because modern hardware is fast enough to do so being an option.

Adding 20% to a 10 second operation is a lot longer on a wall clock than adding 20% to a 1 second operation.

What even is a 20% delta in performance? Like a five year old difference in hardware design.

If I could get a micro kernel with a better security profile than Linux, that doesn’t sound so bad. I could easily be using a ten year old chip for my day to day browsing and probably wouldn’t notice.

If anything, Mach style IPC has gotten worse because of the greater overhead if kernel/user transitions. Spectre really did a number on context switching overhead.