Nuclear weapons, the maxim gun, lead paint, lead gasoline, basically all lead-based products, thalidomide, CFCs, the electric chair, agent orange, asbestos, oxycodone, zyklon b, refined sugar, high fructose corn syrup, disposable plastics, cigarettes, trans fats, ...
I think @PeepinGoodArgs@reddthat.com is doing a great job of pointing to the actual substance of the argument, so I'll leave that to them, but it's actually really easy to come up with a long list of technological horrors that absolutely did not benefit most people but had huge impacts on our economy.
I do think "impact on our economy" is a pretty squishy phrase that'll give you some wiggle room, but many of these nightmare technologies are inextricably and inseparably tied to the way we've structured our economy. Likewise, I think it's easy to define "technology" in convenient ways for these kinds of arguments, but also ends up being circular pretty quick.