Evidently, if you don't update your old Apple stuff, the internet may not work on them after today (Nov 3, 2019). After that, updating will become a bigger hassle (requiring a separate computer and backup/restore). So it might be worthwhile to do the update NOW, while you can still get it over the air.
I am not an Apple person, but we did find some unused old iPhones (a 5, and a 4) and an iPad (3rd generation) laying around that needed this update. We also found a old 5S, which apparently doesn't need an update, but we did one anyway.
Reference:
https://www.cnn.com/2019/10/30/tech/old-apple-product-update-trnd/index.html
I am not an Apple person, but we did find some unused old iPhones (a 5, and a 4) and an iPad (3rd generation) laying around that needed this update. We also found a old 5S, which apparently doesn't need an update, but we did one anyway.
Reference:
https://www.cnn.com/2019/10/30/tech/old-apple-product-update-trnd/index.html