Many websites already have an option to download your data in a parsable format.
The most famous example should be Google Takeout, where you can download your data from any services. My idea is to Steam has an option to download a zip file with all the data.
I know there is an option to view your data, but my idea is also to download too.
I want to have a list of all the games, DLCs, soundtracks, etc. I own on Steam, but today I just can save a PDF or so and that's a little hard to search information automatically than, let's say, a JSON or a CSV file.