Just another sensible decision when it became apparent that even if they wanted him, it was going to cost far too much in relation to the value one player would bring to the team, so they withdrew rather than end up in a bidding war with Real Madrid and end up spending £100m+ and destroying the clubs wage structure for a single player.
And rather than chase the pipe dream all summer and then spank £75m on a deadline day panic buy alternative and nothing else, they replanned in good time and bought four good midfielders that suited the team's requirements and were, as far as I recall, already on their radar.
I appreciate this sort of thing seems alien when you're used to the Man Utd strategy that would have seen them and their pet press bang on about Bellingham right up until 29th August and then **** £75m up the wall on someone else worth about £40m on the 30th August when it's announced he signed for Madrid.