No, the project hasn’t been forgotten. Work continues; if you compare the surface detailing to earlier examples, you can see that a *lot* has happened.
Also note a change in “scale reference” lineup. The Space Shuttle is gone as is the Titan III. In their place is a 747 with stretched upper deck and a “Boeing 2717 SST.” These drawings are to show the state of SSV as of 1999… in the “2001” timeline. Consequently, scale references should be appropriate for that timeline. The shuttle probably wouldn’t have been built; if it had, it would have been retired long before 1999. My presumption is that the Boeing 2707 SST would have been built and become operational by the late 70’s, and would have been replaced with the 2717 sometime in the early/mid 90’s. Also shown is an incomplete Soviet Titov V spaceplane, an incomplete USS Discovery and the “Neptune” booster, which I’ve taken to be a 2 Mlb-payload version of the Convair Nexus. Saturn V included; even though it would have been long since retired, it would be historically important. Especially since it launched Space Station I.