Well, build around is tricky term, so all I can give you is what I mean. When he is fit, he plays. He isn't overly criticized by the manager and if we say that his against the ball-work isn't lazy, the manager grants him certain freedom. He also received very lucrative contracts here. He also appears to show a certain level of selfishness and greedyness that (at least I think that) wouldn't exist when the manager would criticize him for it. Building around also means that the manager accepts some of the negative stuff that comes with every player to have the positive ones. You can accept Bruno giving the ball away all the time because he often does so and produces a chance. Similar to Rashford, you watch him run into blind alleys with the ball 4 times because the 5th time he might push the ball through on goal. I think, that is where the debate really comes from - some think we shouldn't accept those two players negative traits and some others think we should.
That isn't me judging or saying those things are necessarily a mistake but this is the status quo for me. He is our golden boy, he is clearly very talented, is gifted with a great physique and his work mentality seems to be quite good. He also appears to be a good guy off the field. He also over the years has delivered under several coaches and therefor earned his place and stature.
So he earned a degree of intouchable-ness, which potentially lead to him changing his playstyle not for the better. As I said, I think, the club and former managers really didn't do him any favors but the team is bigger than Rashford and for it to maximize its output, he either has to perform at Mbappe level, which would balance out his current negative traits or he needs to adjust. I share some peoples thoughts, maybe he just needs trust in his team mates to re-start creating for others. Lets hope so but as of now, I'd rather take the Rashford of 2020/21 who created loads for others than the 30 goals version of last year.