I watched a lot of Jadon Sancho when he first went to Borussia Dortmund. Early on in his career there, I went to watch them for my 40th. They were playing Augsburg, won 4-3 and he played really well. I got the bug for German football and can't stand Bayern so watched a lot of Dortmund on BT Sports. I found that he looked exceptional when he was up against Augsburg, Hertha Berlin or Darmstadt but not so clever (almost anonymous) when they played Bayern, RB Leipzig or any decent opposition in the Champions League.
Then he came onto the national scene. He did well in a few England matches against Macedonia and the like but again, disappeared when England played anyone of note. Those early England matches made the nation sit up and take notice and I heard many a pundit tell us all how he was THE man in the Bundesliga. You get to a stage where you begin to doubt what you've actually watched with your own eyes because they're ex-players being paid to give an opinion so must know more than me. Then you realise that they probably haven't watched a single Borussia Dortmund match.
When he was coming back to the Premier League, I had reds all around me telling me they were signing the new big thing. I was delighted when he signed for them. Look how that turned out.
I feel the same thing could be happening with Jude Bellingham.