I remember discussing Tintin casting choices with a friend from Germany and remarked how it was odd he often has an English accent in adaptations rather than a Belgian one, and my friend just replied "that's because Tintin gives incredibly strong English boy energy (derogatory)"
Here in the UK there's a lot of weird classism tied into accents. Today accent diversity and representation in broadcasting is actively pursued but in Tintin's time there certainly was a preferred accent to have.
imagine this exchange happens between pages 28-29 in The Crab with the Golden Claws
people who complain about their blorbos having only 4 minutes of screentime are so weak...I'm hyperfocusing on literal background characters with no lines.