Just bought a PS5 last week and as someone who made the transition from PS4 to 5 while playing GT7, I can finally confirm something that has been scratching my head for a while. Back when I played on the PS4 and just watched PS5 gameplays on the internet, I was always wondering: why do the cars sound better on these YouTube videos? I honestly thought I was crazy, because the other day, maybe like 4 or 5 months ago, I asked this question on the Bug Reports thread, but got no answers. This made me believe even more that I was completely nuts, and I couldn't find anyone talking about it here on GTP. If this has been already discussed here, I'm really sorry, but I haven't seen this anywhere.
Turns out the PS5 version really adds an extra effect on the car sounds that make them feel more vivid and aggressive. The sound itself is obviously the same, but like I said, the PS5 version has kind of an echoed overlay effect, and that's mixed up pretty well, it surely makes the PS4 cars sound bland. Keep in mind that I'm not talking about modified exhausts or custom audio settings, there really is a clear difference on car sounds between the PS4 and PS5 versions of GT7. Some of the easiest car examples to notice this if you have the chance and want to compare are the Suzuki Escudo, the Carrera GT or the 918 Spyder, but you'll definitely be able to notice it with every single car.