Slackware

Slackware is the OG of Linux.

http://www.slackware.com/

I started using it in the early 2000's, and I still run it on servers because it is so solid.

There isn't a package manager (by default) that manages dependencies. That is a feature not a bug if you are trying to learn Linux.

The website looks old by modern standards. The releases don't come often but if you look at the changelog's you can see packages are kept up to date. You can also use "current" if you want the bleeding edge stuff.

The packages aren't split up like other distributions, they are simple. Just compressed tar files.

There is no systemd complexity, it is just simple scripts in "/etc/rc.d".

I recommend Ubuntu to those that want to just get started and accomplish their goal. One because there is a lot of tutorials and info out there to search...

But...

If you want to really learn Linux; check it out.