None of the lines of reasoning were an ad hominem. From your other comment[1], it seems like you think "ad hominem" just means "being rude to someone". I recommend reading the GP comment's description of ad hominem again: it means making a logical argument that depends on the speaker's personal characteristics.

"You're European, so your argument is biased and wrong" is an ad hominem. "Your argument is naive, here's why I think that" is not. The latter is logically downstream of the argument, while the former is upstream.

[1] https://news.ycombinator.com/item?id=31854644

no, an ad hominem need not be literal. do you really not understand nuance in language? we're not computers operating only on singular data and deterministic instructions.

see how those three sentences go together? that's a line of reasoning. the subject comment doesn't have that throughline. it's disjointed; the parts are only tangentially connected.

> no, an ad hominem need not be literal

What on earth do you mean by "literal" here? Ad hominem refers to a specific fallacious style of argumentation. Being ignorant of the definition and then too stubborn to admit it is not pushing back against "overliteralism".

Especially because the rest of your comment (dismissing the rest of the argument due to "ad hominem") only makes sense if one assumes the correct definition!

But an ad hominem requires that the argument is thrown out solely based on the attack against the person. Laying out a logical argument against someone's belief, and then _additionally_ insulting him based on his beliefs is not an ad hominem.

A car has multiple parts, but it’s still difficult to use if you only use/look at each one separately

if you look carefully, the 3 sentences are disconnected. they don’t form a line of reasoning.

if it had been starter, engine, and transmission, maybe you’d have a point, but instead it’s corroded battery, door handle, and tailpipe.

I looked at it carefully, and I’m not seeing what you’re seeing unfortunately. I interpreted the naive comment as a separate summary of their opinion, and then the rest of the paragraph was the supporting explanation. He didn’t dismiss the idea because it was naive, it’s the reason it is naive is why he was saying it wouldn’t work

Ah, the ad hominem, never a good sign for the proceeding argument.

None of it was ad hominem.