> I would like to see the metrics

Well, I could regale you with my anecdotes on how all my 'grab a LetsEncrypt cert on Docker deploy and whenever remaining lifetime goes below 75%' services have not had a single TLS-related outage in at least a year, and how we just had a multi-day meltdown caused by a load-bearing cert that everyone forgot about expiring, but I doubt you'll be interested.

I'm not here to take away your right to set up a few more 5-year+ internal CAs (or, hey, how about an entire self-signed hierarchy? can't be that hard...), and neither is LetsEncrypt. But on the Big Bad Internet (where Google is the leading cause of More Security, and LetsEncrypt is merely the leading vendor catering to that), things have moved on slightly.

In circles I'm running in, automatic certificate renewal has not caused a single problem over 7 years of using it, and whatever time was spent on setting it up, has paid many times over, both in saving effort on renewal, and in putting out fires when (not if) someone forgets to renew a certificate. You just have to be careful picking your automation — I haven't been impressed with certbot, for example.

Also, everything is using https now. Living in a low-income country, certificates were too expensive to use them where they weren't absolutely required, but not anymore. This is orthogonal to automation, I'm just pointing out that LE is not as demonic as you make it out to be.

I'm afraid enterprise users are on their own, probably approximately no-one else is interested in going back to the old ways of doing it. (Maybe embedded.)

> I would like to see the metrics on how much time and resources are wasted babysitting all this automation vs. going in and updating a certificate manually once a year and not having to worry the automation will fail in a week.

I have multiple systems. Legacy that I've inherited, and modern that are able to automatically update their certs.

The automated updates require almost zero maintenance, there was a week a couple of years ago when I had to switch some configuration for a new root cert.

The legacy system requires manual installation and multiple weeks of my time every year because of the number of environments, and since generation of the certs requires me to file a request for someone to manually create it, they invariably typo something and it has to be redone everywhere.

So multiple engineers, over multiple weeks?

Manual process at a guess is £50k pa, while the automated is close to an annual £0?

The change in validity does not in any way alter the protocol itself. As mentioned in the linked blog post: if you've already got automated cert renewal, it'll almost certainly require zero change.

After all, the logical approach is to schedule a daily cron job for your renewal process, which only contacts the server when the current cert has less than X days of validity remaining. Scheduling a one-off cron job every, say, 60 days would be extremely error-prone!

With regards to future reductions: the point is to force companies to automate renewal, as they have proven to be unable to renew in time during incidents due to dozens of layers of bureaucracy. 45 days means one renewal a month, which is probably sufficient for that. Anything below 7 days isn't likely to happen, because at that point the industry considers certification revocation unnecessary.

Internal PKI is not relevant here. Anyone with weird internal cert use shouldn't be using public certs anyways, so moving those people to certs backed by self-signed internal CAs is a win. They are free to use whatever validity they want with those.

All the enterprise software needs to do is create an API for configuring the certificate in the product. Then they can integrate Certbot or one of the many other ACME solutions, or let the customer do it (they are enterprises after all).

I'll happily take failed automation with errors I can fix over being totally screwed when we find out the guy who did it every year left the company this year and nobody else knows anything about it.

> A standard protocol with nonstop changing profile requirements at LE's whim. Who's going to keep updating the software every 3 months to keep up?

It really doesn't change that often. And whether this is a "breaking" change is something that's debatable (you shouldn't hard-code the cert lifetime, but I suspect many programs do, so de-facto it may or may not be a breaking change).

If you look at the Go implementation for example (https://github.com/golang/crypto/commits/master/acme), then there haven't been any major changes since it was first written in 2018: just bugfixes and basic maintenance tasks. Maybe I missed a commit but it certainly doesn't require 3-month update cycles. You can probably take that 2018 code and it'll work fine today. And since it doesn't hard-code the 90 days it will continue to work in 2028 when this change is made. So it's more "you need to keep updating the software every decade to keep up".