While CPUs are ridiculously fast, pretty much everything involved in booting a system involves a lot of polling or hard coded waits. Modern peripherals also con

While CPUs are ridiculously fast, pretty much everything involved in booting a system involves a lot of polling or hard coded waits. Modern peripherals also contain only the barest of firmware in ROM and need the drivers to actually upload their operating firmware. No matter how many cores the CPU has or how fast they're clocked they're not going to make all that IO faster. They also can't run a hard coded 10ms sleep faster than 10ms. Even once you get into a booted kernel and PID 1 you're still going to wait on IO to get daemons running. If you've got services (in systemd parlance) waiting on Networking you can have totally variable wait periods depending on local network conditions. SSDs and parallel starting of daemons has improved boot times a lot over the past decade but there's still hard minimums just based on booting up low level crap before the kernel turns things over to PID 1.