GP might have been thinking of things like the inventions of the illustrious Thomas Midgley Jr. and his vigorous promotion of tetraethyl lead, etc.
Yep, that would be a much better example. Defending Midgley is a task for superintelligent AI if there ever was one.
Still, the underlying technology is not "leaded gasoline" but "internal combustion engines." The human condition would certainly be better if you could erase Midgley from history, along with the people who invented shoe-store fluoroscopes and radium paint, but it would be worse if you erased Roentgen, Otto and Diesel. Horses weren't the global-max of mobility and human brains aren't the apotheosis of reason.