I wouldn't agree with that at all. He played in a midfield with Rice and Henderson for the majority of the WC and last night had Rice and Phillips. His job isn't a defensive one. He's there to receive the ball in more attacking space. For Dortmund he's always looking to find little pockets and on the turn can then make things happen, it's a major strength to his game. He's strong and long limbed so even if his touch is bad he often still keeps the ball and then is running at the opposition. With Haaland ahead of him he'll be much more dangerous than with someone like Kane who is often looking to be in that space as well.
We've played Dortmund a few times and Bellingham has been their best player in almost all of those games. He's been an attacking threat and he's also been at the back putting in tackles and defending.
He's much more likely to move into space to score or provide an assist than be the one controlling the tempo of a game, but I still believe he can be moulded into whatever we specifically need. It's much easier to learn to keep the ball and find others in space than it is to learn to turn and spin past players before carrying the ball and creating a chance.
It's a bit like Kev's form recently. Pep just reminded him to do the simple things first, and funnily enough he did and then the through balls and assists came again.