Some distro install and enable services that you would never use. Red Hat Enterprise Linux (and Fedora?) enable the cups printing daemon (I never do printing on Linux and I use a canon lbp 3300, I have to install drivers on windows). Ubuntu enable the openvpn service which "newbies" would never use.
But none of them have tmux installed by default, while OpenBSD have tmux, if I recall correctly NetBSD too
Very important. Don't run arbitrary commands on the internet, but don't paste sysctls and config too.
Linux lacks much documentation. Man pages, tutorials from arch and gentoo wiki should be considered.
that's my feedback