We now know it as "the web".

But originally it was "the World Wide Web": a much longer and more distinctive phrase.

Over time, as it became more and more obvious that we were talking about the World Wide Web, it became less and less important to have the signifiers.

More and more people could safely elide the "World Wide," confident that their listener would know what they meant.

It's possible to start with a specific, qualified name, and once it becomes society-scale, the qualifiers fade away.

Just "the web". It's cleaner.