TOS is profoundly ambivalent about technology and computers in particular. Yeah, they have all their shiny futuristic toys, but a certain unease keeps creeping in. See also: "Court-Martial," "The Ultimate Computer," "The Changeling," "A Taste of Armageddon," and all those episodes where Kirk defeats an evil god-like computer.
And it's not just McCoy who voices these concerns. You also have Samuel Cogley orating about man vs. machine, the space hippies in "Way To Eden," and even Lenore Karidian complaining that technology has made people more like machines. (Okay, she's insane, but . . . .)
People were definitely worried about these issues back then. Remember HAL in 2001?
And Colossus: The Forbin Project?
And Demon Seed