One of the big differences was that GT4 was released by PD in the knowledge that they COULDN'T patch it. Q&A was taken FAR more seriously, and playtesting seems to have been complete before release.
GT5 was released DELIBERATELY early, in the knowledge that it COULD be patched.
So, on the old GT4 forum, there really wasn't much POINT in complaining, because nothing could be done about it, and it was far better playtested in the first place.
So, a large part of the 'complaints' (and boy, I just LOVE it when legitimate complaints are dismissed as 'whining' by fanboys content with mediocrity) is because we KNOW that these issues (or many of them, at least) COULD be fixed by PD. And, as Kaz doesn't exactly answer my emails, THIS is the place to come to voice our needs.
To annswer the OP...
NO, it didn't. Because it didn't NEED to.