I've got a very old iPad, around 8 years old.
It was working ok, just a bit slow. I had Netflix and Amazon prime apps on it which worked ok.
I took it into the Apple store recently for advice about the speed. They said they would do a factory reset to try and improve it. They warned me I would lose things like photos (didn't have many on there anyway) and I would have to re-download my apps. I agreed to this.
However when I tried to re-download Netflix and Prime, it wasn't possible as the software wasn't compatible or something. I've been on the phone to them and they said there is nothing they can do as it's a 'vintage' iPad.
I said if they'd warned me that I wouldn't be able to use Netflix or Prime any more I wouldn't have agreed to the reset.