If cars were invented today, they would be too dangerous to be allowed to exist. Almost nothing has been invented since 1970 that can cause any harm. Safety first and all that.
They'd have to be built with cow-catcher like devices to push all the horseshit out of their way while traveling down the road. It'd be a different kind of awful.
Personal computers cause all kinds of harm (in addition to the benefits).
Not much physical harm and very little liability. I think computers and software was the one place people could make what they wanted and sell it without much worry of getting sued out of existence and that is why there was so much advancement. Software licenses are pretty amazing with the "as is" clause that seems to hold up.