In the 20st century serious intellectual thought mostly became thought backed up by academia. Academia then had a custom that it didn't really like interdisciplinary departments but it tried to organize itself into nonoverlapping departments. Many departments were also pressured into doing research that's directly useful to corporations and that can produce patents.

General Semantics and also Cybernetics are fields that lost as a result.

I think there a good case that times change. With the Giving Pledge there a lot of Billionaire money that wants to fund new structures. OpenAI is one example of a well funded projected that likely wouldn't have existed in that form in the past. Sam Altman also wants to fund other similar research projects.

The OpenPhilantrophy project is sitting on a lot of money that it wants to funnel into effective project without caring at all about departmental overlapping.

A world where a lot of people live in their own filter bubble instead of living in the bubble created by mainstream media might also lack what we call mainstream at the moment. Yesterday I was at a Circling meetup in Berlin. I also read at the same day about the experience of an old Facebook friend that lives in the US that did a circling trainers training. In my filter bouble Circling is a global trend at the moment but that doesn't mean that it's mainstream.

If we look at general semantics it's also worth noting that it both succeeded and failed. The phrase "The map is not the territory" is very influential. Neuro-linguistic Programming (NLP) is named that way because of Korzybski usage of the term neuro-linguistic. NLP is based on general semantics but it evolved a lot from that point. NLP is today an influential intellectual framework outside of the academic mainstream.