The concept will re-emerge somehow. Webpages are 99.99% of the time the formatting of a data structure for humans. LLM can barely infer that data structure from the webpage and connect it with other data structure of other pages. [truth is that the LLM algorithm does not do that AT ALL internally, but from our user experience it really looks like it does].
But when webpages die and data is accessed only by machine2machine APIs, we will no longer have this formatting for humans. Then we will need API-literate LLMs. Which means LLMs that can connect the dots between shitloads of unconnected JSONs. And if we don’t hint it for which connections are existing between that chaos of APIs, it will not be able to apply its magic. In short: we need to be able to bring JSON to vector space. And it is absolutely not meant for that, by default.
I agree that something like it will re-emerge. But I also think the semantic web has always been misunderstood and misapplied even by its proponents.
In my view, semantic web technologies should have been used to make databases interoperable, not to turn the hypertext web into an incredibly incomplete distributed database without any data quality process.