There are a lot of big, messy, "terrible" applications with dumb dependencies that seem to live far longer than they "should". It's mostly in large companies but not really related to these companies. These same applications usually have unique functionalities and user who have become expert in the use of apps, including knowing the "stupid parts".
Writing these apps is hard and it's a completely rational decision to jury-rig deprecated libraries to make such an app work however irrational it might look from the outside.
Oh, I'm totally aware of technical debt, etc. I have worked on both maintaining and rewriting a number of such enterprise apps myself. It is just in this case, if the revenue WAS ever at risk (don't forget we are talking billions here), then you would need to be a bungling idiot to not fix the issue at hand before embarking on a rewrite.
Personally, I think the article is a dramatisation - I would certainly be too embarrassed to write such a thing if it were true.
Writing these apps is hard and it's a completely rational decision to jury-rig deprecated libraries to make such an app work however irrational it might look from the outside.