I think it would depend who they were and what/who they knew. Political will wasn’t all that great for the moon, Kennedy even invited Russia to make it a joint venture multiple times more or less to save face while splitting the costs (in the 60s, but still). If Kennedy hadn’t been assassinated there’s a very good chance it wouldn’t have happened when it did and it would be seen as Kennedy’s folly or something.

So someone in the late 50s who was familiar with the actual feelings around budgets and such, might not be so surprised.