A bog standard Linux distribution boots under 30 seconds with a good HDD, assuming hardware initializes fast.
SSD generally adds 3x to that speed due to access latency for small files.
I remember pressing power button and leaving my PC alone to get a tea or something when I was booting my Windows installation which I had around for gaming. Same with an SSD. Desktop arrives faster, CPU still choked to launch whatever services are needed, fans are doubling as hair dryers.