The upgrade mechanism on a typical Linux distribution is _even more_ gloriously simple, and exactly the same as it has been for many years.
# Fedora/RHEL
$ sudo dnf upgrade -y
# Debian/Ubuntu
$ sudo apt update && sudo apt upgrade -y
# Arch Linux
$ sudo pacman -Syu
The false distinction between the OS packages and user local (/usr/local) packages during upgrade causes much unneeded complexity. FreeBSD is making this go away which is welcome.