It's the iOS app support that suffers. Apple makes it pretty unbearable to get apps for unsupported devices so I take those and relegate them to single use non-data holding devices like dashcams and other uses.
As of at least a couple of years ago, I could still redownload “the last compatible version” for my old iPad 1st gen (2010). I was able to download and run Netflix and Plex.
Yes, but you must have a nicer iPhone on the same iCloud account that downloads the current version, then you can use the "purchased" page on the old device.
