[davmre]

I doubt they included it on either side. How many Linux vendors still offer security updates for distributions from 2001, at any price?

As others have pointed out, paying for support is likely much cheaper and less disruptive than developing, re-testing and re-verifying new versions of their systems. "If it ain't broke, don't fix it." I'd imagine when they do eventually migrate they'll try to stay on the new systems for as long as possible, as well.

[kwijibob]

I'm sure Red Hat would welcome a defense contract that pays over a decade. They might even have a couple already.

[honest_joe]

And you would really want a Red Hat a company and system notoriously known for being bad at security ? (check Bradley Spengler vs Red Hat)