It doesn't fall flat, it just (potentially) shows a net benefit for most. You've also narrowed the debate to a purely materialistic benefit (.i.e. more things cheaper) while taking a broader view of the whole class of people at a time.

An individual does not have the luxury of evaluating the "good of the many" when they are unemployed by innovation. Equally horrid from the individual's perspective is discovering the skills they've spent a life time accruing are suddenly worthless and make them unhireable.

White-collar workers have only just started feeling this pressure of good jobs disappearing only leaving more menial and lower-paid jobs.

To ignore that some people are harmed by innovation is as silly as pretending that all innovation is a positive.

It's also important to note that you can't just credit changes in living standard to technological innovation. Soft innovations in things like politics and philosophy are AT LEAST as important as technological innovation.