Well, you could just change all the names and remove all explicit references to the original and then sell it. I was just looking at the new game Tempest Rising, which is extremely obvious about copying the plot and design of Command and Conquer, but it’s been changed just enough to avoid copyright.
I’m not sure where you’re numbers are coming from, but the inflation calculator I found through Google says that $59 in 1992 is more like $135 today. That’s still a significant increase of course, although I wonder how much publishers benefit from not needing as much physical distribution. After the initial investment selling digital keys on a third-party storefront like Steam should be pure profit, no?