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Sony is killing off recordable Blu-ray, bidding farewell to disc burning | TechSpot
(www.techspot.com)
This is a most excellent place for technology news and articles.
"Required" might not be the right word, but here's an article about how the San Fransico Trains are updated via floppies - https://www.wired.com/story/san-francisco-muni-trains-floppy-disks/
In the US at least it's not about required, but more legacy support. There are still a lot of old systems that work, but use old technology.