Interesting that the article offers no alternatives to Google Photos. I know there are options, but they all seem to be far behind in terms of features. Plus, migrating all of my photos out of Google Photos would be pain.
Photo seems to be part of takeout : https://takeout.google.com/settings/takeout
I have not tried it for photo but it seems like you can download all your albums.
One thing that Google is exemplary at in my experience is in providing an easy way to export all your data if you want to.
You can export them (incl. meta data) through the regular Google Takeout. From there you just have to upload them again to your new, preferred cloud provider.