I ran Gentoo Linux 2003 to about 2008. I initially picked it up because of a hype. However, I loved the degree of customisation over the system that I got at the time. The install process teaches you of alternatives to things that distributions would include. It gave me a lot more choice as to what I used with my system and the process of installing. It definitely made me understand how the system worked a lot more.

I reinstalled it 2023 and I'm still using it too today. My reasons are different now. One is a hint of nostalgia. However, another is the package manager. Since the package manager is only text files, it is very easy to extend and change with your own packages. Releasing packages on other systems is much more involved process.

Another reason is when you compile the code yourself you can choose the options to some it degree with use flags. I still build my own kernel as I can choose what to include and I think I will be moving to a unified Kernel in efi soon and do away with grub.

Using Gentoo compared to most other distributions the system feels more open and more malleable.

While I do consider arch rather similar and I did use it for a couple years. The AUR scared me a bit.