I spent plenty of time reading (and enjoyed!) on Wikipedia, about MINIX (1/2/3). microkernels, monolithic kernels, genode audit/builder concepts.
I just opened a can of worms: so much info about alternative CPU types, security, various Unix OS flavors.
It could take me months just to read this sort of material, without doing something else (like walking, smell flowers, listen to music/birds, gain money
)
I would prefer a slower and secure microkernel, instead of a faster and compromised monolithic kernel. Anyway today CPUs are a lot faster than my normal needs.
I am a user, not a developer (to audit the appl., the system) and I
prefer to just use appl. ready made. My time is (relatively) limited, and I need to chose wisely how to invest it.