> In the enterprise space, if you mention globally reachable address space, the discussion tends to end pretty fast because “its not secure”.

Topic drift, but for younger people who didn't live it, that's how it used to be!

For most of the 90s my workstation in the office (at several employers) was directly on the Internet. There were no firewalls, no filtering of any kind. I ran my email server on my desktop workstation to receive all emails, both from "internal" (but there was no "internal" really, since every host was on the Internet) people and anyone in the world. I ran my web server on that same workstation, accessible to the whole Internet.

That was the norm, the Internet was completely peer to peer. Good times.