Going by my observations, it's not always the case, and it depends a lot on what's been put in (input) and the expected returns (output); people can put in quite a lot of effort into whatsoever they are doing, but with little end product. The thing is, OP you're mistaken 'hard work' for efficiency, the fact that one engages in menial jobs doesn't mean such person is putting in an awful amount of effort into what they are doing, and even if they are, then output would not be sufficient cause the input is prolly not what is required by the society in such a given time.

Having said that, individuals who 'work smart' may not look like they are putting in an awful amount of effort into what they are doing, but they actually are, what society needs right now is solution to problems, and it's the individuals who 'work smart' that provides such solution, take the case of Bitcoin, the effort and hard work put in by Satoshi must have been enormous, but it wasn't open for everyone to see, but the output speaks for itself as it solved quite a lot of problems when it comes to finance.