I think it's important to point out that MUDs were probably the first complicated interactive synchronous "Internet applications", even though they were (primarily) textually driven and not "serious" (they were to us). So things like Pike (née-LPC) & moo were on the forefront here on how to author those kind of dynamic systems.

Early web sites, gopher, etc were just request/response mostly static content (sometimes with a dash of a database). They weren't synchronous or "live" in any real way. Things like IRC were synchronous but did not do programmable/dynamic content.

I cut my teeth on moo, and was bored & annoyed to tears writing cgi scripts in Python & Perl and the web didn't catch up to produce really interactive stuff until well over 10 years later ("web 2.0")