When I worked for Shell I saw a few engines running on computerised test programmes and they were inside a so called sound proof cell. A big ICE at full chat defeated the sound proofing!
I would agree that most manufacturers attempt to fit sufficient sound deadening. However, after owning 8 Hondas, I have come to the conclusion that the Japanese enjoy excessive road, wind and engine noise on most models. My HR-V e:HEV was very noisy and now I am driving a CR-V SR e:HEV it is much quieter than the HR-V but still too much tyre roar, which is, I am sure, in the main, down to the cr@p road surfaces we have in the U.K.