That's only one way to look at it. There are lots of weird integrations and third-party products that OS vendors have to account for in a decision like this. I

That's only one way to look at it. There are lots of weird integrations and third-party products that OS vendors have to account for in a decision like this. I don't know how they set dates for end-of-life on their products, but many vendors are obligated to provide support longer than a reasonable person might expect.