I remember when I was an intern during college I asked a mentor how do I learn more about operating systems and Linux. He told me to just install Arch on my laptop.

This is a point that gets missed a lot. Besides the benefits of having a minimal system and the rolling releases, installing Arch will give you a really good understanding of how the OS works as well as information of process management, file systems and other lower-level components. And it's cheaper than going through 4 years of a Computer Science degree ;)