This made me think of a specific instance of hindsight bias that always annoys me. Consider any game of chance where at some point the person is given the choice of whether to make a wager or not.
Once they see how the wager would have turned out one is almost guaranteed that if the wager would have won they’ll say to make the wager would be the right decision and if the wager would have lost vice-versa. This holds even if they were already aware of the odds before hand.
I think the graph comparison isn’t a completely valid metaphor. With the graph you describe the relationship between two nodes is binary, either it’s present or absent. But between topics there are numerous types of connections, for sure the statement “everything is connected” conveys no useful information but I believe that it’s very difficult to find two topics with no type of connection. For instance Wikipedia couldn’t be considered an artificial intelligence but I would not be surprised if there are certain topics in artificial intelligence that could be applied to wikipedia (associations between topics could be a possibility though I don’t know enough about AI to know if that would be useful). For instance simply drawing an edge from AI to Wikipedia tells little, but perhaps 3 unique edges describing the precise connections could be very informative. In this way one can achieve a connected graph that still is very informative.