Physics–the only science where reductionism ever really worked–has sort-of ruined it for all the others, where it (mostly) doesn't.
In economics, you are studying vast systems. For the majority of questions, it is impossible to isolate some part of the system and control and measure all the inputs and outcomes. That's probably obvious for macroeconomics: You can't have FED raise or lower interest rates based on a random number generator. And even if you could, you would still need a second United States to act as the control group.
It's mostly also true for microeconomics. Consider the difficulty of studying UBI. The largest such studies gave a basic income to a small African village, for a limited time of maybe two years. But the idea, and its opponents, mostly deal with the life choices people make, requiring essentially life-long guarantees. And even just knowing to be part of such a study, or continuing to live in a society that hasn't changed, is likely or at least plausible to change the outcome to render the study meaningless.
In economics, you are studying vast systems. For the majority of questions, it is impossible to isolate some part of the system and control and measure all the inputs and outcomes. That's probably obvious for macroeconomics: You can't have FED raise or lower interest rates based on a random number generator. And even if you could, you would still need a second United States to act as the control group.
It's mostly also true for microeconomics. Consider the difficulty of studying UBI. The largest such studies gave a basic income to a small African village, for a limited time of maybe two years. But the idea, and its opponents, mostly deal with the life choices people make, requiring essentially life-long guarantees. And even just knowing to be part of such a study, or continuing to live in a society that hasn't changed, is likely or at least plausible to change the outcome to render the study meaningless.