Don't be ridiculous. That does not make "You are doing god's work, son. Thank you." any less ad hominem, nor do you actually demonstrate any reasons. Your argument amounts to "copy+paste coding is bad, therefore your codebase is bad", yet at no point explains why. But keep downvoting anyone who points that out :)
An ad hominem argument is one in which you reject a position not on its merits but because of who is making it. They took a position that copy/pasting code leads to unmaintainable code, therefore his argument is not ad hominem.
He's being insulting, sure, but that doesn't mean he's making an ad hominem argument.
I've seen that more from guys that "start from scratch" than guys who cut and paste... most guys who cut and paste also annotate and comment... most geniuses can't be bothered to both code and comment...
> whole teams grind to a halt productivity-wise because the codebase is so bad