Interesting question! I’ve been thinking about it also, but so far did nothing about it.
But thanks to your question, I decided to write a little script that shows what Arch pages choose to reveal as the change logs for any official Arch package.
Usage is simple:
on a terminal, and it shows you the change log of that package in a browser.
Note that you need to know the exact package name – e.g. libreoffice-fresh instead of just libreoffice.
Note also that this does not show changelogs about AUR packages nor Antergos packages.
You may configure it (use your favorite browser) by changing the BROWSER_ARCH_CL environment variable, e.g.
in your ~/.bashrc file. But don’t have to configure, it works by default anyway.
EDIT: I removed the script from here. Please download and install it using these commands:
cd /tmp # or any folder you have write permissions
wget -q https://github.com/manuel-192/arch-cl/raw/master/PKGBUILD
rm -f PKGBUILD arch-cl-* # optional cleanup