A scuttle full of coal in a modern train in the fuel area would also be an anachronism. So would a horse and buggy on the interstate. Or a mace on a battlefield between 1st world countries. Anachronisms are something that doesn’t match the time in either direction, which is why the word is older than stories about time travel.
However, objects from the past routinely appear in our present. In museums, they're called artifacts. Around my home they're called “that pile of old junk in the basement I'm going to get rid of with a yard sale”.
You used the term critically — as if the wrench appearing in TOS were equivalent to (say) an iPhone appearing in a production of Hamlet. Really, that was not a valid criticism. For instance, Scotty might be a collector of historic mechanic's tools. He might call them artifacts, he might call them “my precious” — but, he'd never call them anachronisms.