(I'm sure it is.)
"Is the style guide they use for internal projects the same as this style guide that they have published externally?"
"could you clarify which ones you're talking about?"
"Is the internal style guide you described the same as this one I found in google's account on github?"
"oh, I see what you mean"
will you send your second, or shall we simply pistols-at-dawn?
The fact that you put "internal" in quotes suggested to me a mild level of sarcasm or disbelief, i.e, I read your message as "You mean this style guide, published on the internet, for all to see? Clearly that's not 'internal'!"
Either way, to me, "internal style guide" (regardless of any quotes placed around any word) means "style guide that is internal" (that is, the style guide itself is private or unpublished).
But the person you were replying to called it a "style guide for internal c++ code": that word ordering makes it clear that "internal" is describing "c++ projects", and that the internal/external (or unpublished/published or private/public) status of the style guide itself is not being talked about at all.
(As an aside, if the commenter upthread had instead said "internal style guide for c++ code", that could have also meant the same thing, but would have been ambiguous, as it wouldn't have been clear if "internal" was describing "style guide" or "c++ code", or both, even. But "style guide for internal c++ code" is about as unambiguous as you can get.)
Whereas the respondent said this:
> Google has a “style guide” for internal c++ code
This is a style guide for definitely-internal c++ code, with the internality of the style guide itself unspecified. I'm not sure what the effect of the scare quotes around "style guide" is meant to be, just that it doesn't move the internal part next to the style guide part.
Putting the whole thing in quotes, rather than just "internal", questions whether the guide you found is the guide referred to, rather than the internal nature of the style guide itself, which the quoted sentence takes no position on.
This has been your daily dose of Hacker News style guides for discussing style guides.
Consider that the style guide that AirBnB uses for internal projects is not the same as the style guide they publish externally, and you can sympathize with why the distinction matters :P.