Or to put it more elegantly: "Stop there! Your theory is confined to that which is seen; it takes no account of that which is not seen."
True, but if you're talking opportunity costs then I see Apollo, and the space race in general, as a great success story. They took the polotical atmosphere of nationalism, paranoia, one-upmanship, costly signalling, etc. and funnelled some of it into exploration, science and engineering at otherwise unthinkable levels.
It it weren't for the space race, it's likely the majority of those resources would be poured into armaments, military-industrial churn, espionage, corruption/lobbying, (proxy) wars, etc.
Sounds like a bargain to me.
The problem with this type of attitude is that discovery doesn't work like this. Incremental improvements can sometimes work this way, but big discoveries do not. If there had been a mandate to "find a way to communicate without wires" I'm going to guess that it would not have gotten very far. Instead, this came about as a side effect of pure science research.
That said, I do take chriswarbo's point that it could have easily instead been even more baroque weapons or proxy wars, as well as yours and manaskarekar's about the uncertainty inherent in counterfactuals. I just wanted to make the point just finding some positives is not enough, you need to look at opportunity costs. If we both look at them and come to different conclusions, that's life, but at least we agree on the basis of measurement.
It's definitely debatable and hard to gauge. I just thought I'd throw in the link to show the other side of the argument.
