Earlier quoted context omitted.
The "old" internet was all static or lightly server-rendered pages, that can be developed and hosted at minimal cost today. Back in the day we didn't expect that "everyone" would sign up for whatever niche forum you were hosting, it was enough to have "everyone who's into that niche". These services don't need "monetization", they can be kept up with minimal amounts of crowdfunding, while federating through well-know…
The actual "old" Internet is the stuff that predated the web: Gopher, IRC, Usenet, MUDs, Public Access Unix systems, telnet...
(Do you know my first post on Usenet (using a NNTP client program I wrote myself, actually) was in 2019? I still use it, although there aren't a lot of messages on there, but there still are some.)
I suggest if you wanted to make up a web forum or mailing list, to set up a NNTP instead please. I also invented Unusenet which is a way to form newsgroup names which are not part of Usenet (you can have both on the same server; the names never interfere). You could also have multiple interfaces to the same messages if wanted, making more use better.
With other protocols too (such as IRC), a bridge can be done. For many kind of text-basedinteractive uses, telnet (or SSH) is much better than using a web page.