This post fits a pattern of a lot of (bad) anti-econ posts. You raise a question, declare the "econ" answer to be something simple you've heard, then say that can't be right because of various considerations that occurred to you, and end with a sage "its all so very complex" without offering any alternative concrete estimate. But what you call the "econ" answer is just the first, simplest econ answer - most of the considerations you raise are known to economists, who use them to create more refined estimates. You are just reinventing the wheel here - if you really want to contribute to social progress on this issue, go learn some econ.