Speed of a package manager should never be a major concern nowadays.
I would like to disagree with this. It's not just updates. Sometimes I add and remove a bunch of packages back to back to test stuff out or check soft dependencies or pull/remove dependencies for projects I am checking out and compiling or switch between prepackaged/compiled versions. For example I was once testing the difference between wine and wine-stable-ubuntu in combination with winetricks installed/uninstalled. That is four configurations and you might visit each one more than once. I once saw a classmate use the fedora package manager in real life and I thought it was quite slow. I am happy with pacman, it really rips through packages which is convenient.