It didn't "fail." It didn't take off. There are plenty of tendrils of the original ideas remaining, and ultimately its main idea, that information should be relatively typed so it's more precise and reusable, is likely to prevail. The requirements were obviously too much for the web environment of the 2000s, and we're still suffering with startup culture where everyone wants to get rich with a piece of the pie, so guessificial intelligence is pretending to fill the gap, but hopefully all the problems with stopgap approaches will finally make the mainstream switch back to widely intentionally creating information.
First, I agree and would also like to say the semantic web idea is roughly 25 years old, which is such a short time period that saying something is dead/failed seems a little silly.
Second, I would say the idea is more realistic now than ever.
Now we have:
- Git so you can cheaply & collaboratively experiment + evolve both data encodings and schemas
- Faster, more reliable type checkers and code/data refactoring tools
- Deep learning agents that are showing promising gains in question/answering challenges so I can see in the very near feature DLAs coauthoring semantic content alongside humans
- As always, more programmers, faster bandwidth, more data, faster computers, etc.
I think technology is getting to the point where the semantic web could happen relatively quickly.
That being said, I still don't know if it will happen because I now am not sure if there is are strong economics forces that would impede such a thing.
