When a new technology promises large private benefits but may impose social costs that markets do not price, demand need not reveal how citizens want it governed. We examine this in a nationally representative U.S. survey experiment (N=5,556) on human enhancement technologies (HET). Vignettes randomize benefit domain, mechanism, heritability, purpose, and risk; we elicit stated adoption, preferred regulation, and ethical and societal concerns. About 53% would adopt. An enhancing rather than restorative framing lowers adoption by about five percentage points, as much as a severe side-effect profile. About 28% would not adopt at any benefit, a refusal driven overwhelmingly by the enhancing framing, not risk, consistent with a non-compensatory constraint. Most who would adopt still favor strict regulation, and most who would never adopt do not wish to forbid others. Productivity enhancement generates the most ethical concern but attracts the least regulation, and respondents favor subsidizing rather than taxing its adoption, consistent with a concern about access rather than safety. Private demand is an unreliable guide to the governance citizens want, informing regulators seeking to align technical change with societal values.