Jotaro and co not hearing Josuke is a lot more justified in the manga.
The distance between both groups is not directly shown, and the manga puts more emphasis on the pouring rain
So, speaking of the one complaint that I'm seeing brought up most frequently with regards to this episode e.g. Jotaro seeming ignoring a battle that's going on next to him, I feel like the biggest problem is not the visual representation of the space. It's the audio.
The manga does not have this problem because the way that the information is conveyed to us is very clear. As you can see in the manga panels above, we're explicitly shown that Jotaro doesn't actually hear the fight. How do we know this?
Fact 1 - The panel with Jotaro's reaction in does not also feature Josuke's scream. It's not included as a sound bubble.
Fact 2 - The panel also tells us that the rain is very loud.
Interpretation - From the information presented on the page, the reader then forms an interpretation of the events in their
mind - namely that Jotaro can't hear what's going on because the rain is loud.
The anime screws up this very simple logic in a clumsy way.
The scene beings with Josuke screaming:
The audio of Josuke screaming continues, and the camera travels towards Jotaro,
demonstrating that the sound is travelling towards him:
We cut to Jotaro, and the audio of Josuke's scream is
still playing. Jotaro then reacts to the noise:
As you can see, this is a fundamental mistake because the show is
literally tells us that Jotaro heard the scream by playing the scream over the visual of him reacting. In the traditional language of film, when audio is used in this manner we take it to mean that the character can hear it. Moreover, while it is also raining in the anime adaptation, the sound of the rain isn't particularly loud, and we can clearly hear the scream over the rain.
In addition, the use of the moving camera timed with the audio implies the sound is travelling towards Jotaro, whereas in the manga the layout of the manga panels does not imply this at all.
The adaptation changes the scene from Jotaro literally not hearing Josuke to Jotaro literally hearing him.
This decision the creates an apparent character inconsistency for Jotaro, because we know from experience that Jotaro is a very thorough and dedicated character who would surely have investigated this noise if he could hear it as clearly as the anime implies.
