It sure is! King Crimson's power tends to do that. (I think.)
…wait, did you mean it some other way?

Not making any judgement on the quality of the part, he's right though. Nearly every other part introduces or concludes some concept used in another part. If you skip part 1, you miss out on hamon, the stone mask, and the origin story of Dio. If you skip part 2, you miss out on the origins of the stone mask and young Joseph Joestar. If you skip part 3, you miss out on stands and the death of Dio. If you skip part 4 you miss out on the introduction of the arrows. If you skip out on part 5, you miss out on nothing. No concept or character introduced in part 5 makes it out of the part. You could go from the end of part 4 to the beginning of part 6, and you would know everything you need to know.

Granted that's to say you can, not that you should. But I know past Vento Aureo translations were bad and are still probably in circulation, plus DP anime adaption's most definitely coming up soon, so I don't think it would be an awful suggestion to say you can skip part 5 and even my beloved part 6 and come back to them when they're animated.

But you should still witness some form of Part 5, because even if you want to bitch about it, you should know first hand what you're bitching about.