I have had this question for years myself, and I still think it has a lot of potential for companies. For new tech to take off, multiple things need to be true

I have had this question for years myself, and I still think it has a lot of potential for companies. For new tech to take off, multiple things need to be true and often the social factors are the most important. The semantic web tech seems mostly driven by scientists and highly specialist companies. The barrier for developers is still quite high and a lot of concerns have been poorly addressed. Probably the most important merit of json-ld is improving the usability for developers a bit, making it less difficult to take advantage of the semantic web. Furthermore, most organizations subdivide the work in silos (teams) and have clear subdivision of goals. Anything you are doing that isn't directly contributing to the goals assigned to you or your team is potentially damaging your standing and rewards, whether those are promotional, monetary or simply recognition and praise. After all, this effort cannot be spend in your main focus. So this comes together with my previous point: it takes a lot of 'extra' time adapting the data in your silo to work with the semantic web of your company, and there are usually zero incentives for doing so. This is true even if it would be quite valuable to the company as a whole, because individuals and teams don't act from that perspective. Thus, it simply doesn't get done, since it only really works if (nearly) everybody is onboard. Its like the famous decree of Jeff Bezos demanding everything to be available via an api: it takes a single minded visionary (or dictator) to push everyone to do this 'extra' work and get to the point where the investment pays off.