Now that I think about it I have seen computer running an OS like that, but only for the machine that was running the Oracle database that let the CTO get his golf buddy a $50k/month sale, never on one that was actually being used to do something.

This is standard operating procedure for financial institutions in Europe, at least. And many, many other types of enterprises.

For core banking and other mission critical systems. Nobody upgrades an OS for fun, especially when the checklist for doing so is longer than both my arms put together.

Not every financial institution in Europe, I assure you. The one I worked with actually had a policy that anything that hadn't been updated in six months had to be signed off as it was considered a risk factor.

I think we might be talking past each other and you may have missed the original point.

This is not about security updates.

This is about using old, but still updated LTS/enterprise versions.

I don't know <<any>> enterprise mandating upgrade to the latest LTS within 6 months. Most do it 6 months before the old LTS period will expire :-))

Hmm. The policy was "a release published in the last 6 months", which sure, could theoretically be an old LTS branch. There certainly wasn't a culture of doing that though. I remember a huge scramble to move everything over to Java 11 (honestly a lot scarier than an OS upgrade in that context) which I'm pretty sure was based around 6 months after the first release of Java 11 rather than the EOL date for Java 8, but it's possible those were the same thing.

Well, I'll tell you how I know the policy I'm talking about is more popular than the one you're talking about: LTSes themselves, and vendors offering extended, enterprise support for old software in general and OSes in particular.

If enterprises would consistently and massively upgrade early (for example within 1 year of a new release), vendors wouldn't need to offer this super long support on such a widespread scale. There's a reason Windows Server is supported for so many years, or RHEL, or SLES, or Solaris, or whatever.

It's popular if you weight by dollar spend, sure. That doesn't mean it's popular if you're weighting by actual productivity.