My conclusion is that microkernels offer some protection from random reboots, but not much against hacking

Say the USB system runs in its own isolated process. Great, but if someone pwns the USB process they can change disk contents, intercept and inject keystrokes, etc. You can usually leverage that into a whole system compromise.

Same with most subsystems: GPU, network, file system process compromises are all easily leveraged to pwn the whole system.

Year of HURD on the desktop?

Of course by now processor manufacturers decided that blowing holes into the CPUs security model to make it go faster was the way to go. So your micro kernel is stuck on a hardware security model that looks like swiss cheese and smells like Surströmming.

How are SEL4 and Genode going for you in your day-to-day compute usage?

Yeah cause windows is amazing Or maybe macos? Ignore their freebsd parts of course.