What’s the origin of the phrase “Good shit”? And “Holy shit”?
Within the next year or so, there will be published the third and final? volume of The Historical Dictionary of American Slang which is kinda the authority on this kind of stuff. “S” words will be there.
Until then, I can only say that “good shit” probably is a late 20th century phrase. “Holy Shit” could have come about in the earlier 20th century, as many an expression using ‘holy’ came about. There are 19th century ‘holy’ uses, but ‘holy shit’ probably only became popular in the 20th C.