I had the same response to 1e Runebound, although it was not my sunk cost. A friend of mine bought all this stuff and we played it all the time. Then he moved away and gave the game to another friend, who still has it after about 7 years, and we’ve never played it since. Every time it gets mentioned, I have to point out that it’s just not very much fun, and we could probably play a dozen games of Codenames in the same time.