Worse goals stats than Son, but significantly better assist stats. However, all Sancho's stats come from the Bundesliga where opposition teams are of generally lower quality compared to the Prem. And his 13 England appearances so far have been OK, but nothing more than this. Of greater relevance, I'm not arguing that Son is worth £108m.
I've seen it all before. People get carried away with fancy tricks and dribbling ... and ignore many other aspects - including "boring" things like professionalism, character, hard work, dedication (I'm not saying that Sancho lacks these things) - of what combines to make a player truly great. This is why a player like Neymar, for all his dribbling ability, is inferior to a player like Kane IMO.