> 3) custom hardware firewalls.

In this case, “custom” means firewalls made by pretty much any of the major vendors.

Cisco, Juniper, Fortinet and Palo Alto have a lot to answer for with their laziness. Cisco and Fortinet added support only recently. Palo and Juniper haven’t bothered at all.

Even plain IIS still doesn't support ACME on Windows Server 2025 without you grabbing some random scripts off the Internet written by people you don't know.

But yeah a lot of Windows server software uses inbuilt web servers with no ability to tweak or tamper beyond what the application exposes in its own settings panel.