Putting aside his off-field issues, he's going to want big wages and is already 27. For a team that's going nowhere this year, I'm not sure he makes a ton of sense. Him helping us finish 8th rather than 11th doesn't really move the needle.
Likely he'll start declining within the next couple years (fullbacks
peak on average between 24 to 26, so he may already be in his decline phase), and very likely he'll be considered an "overpaid" player that needs to be shipped out by the time our roster is really good. For an Arsenal who just needs an extra piece or two he could make sense; for a team that's miles off I'm not sure how adding players like him on big wages makes our future brighter. He's a "win now" player when we have no realistic chance to do that; we should be buying 22-24 year olds who can grow with the team IMO. That's how most long-term winners are built, and United's been buying older guys for years to our own detriment.
I see people linking us to guys like him and Antonee Robinson and I just can't help but shake my head. It seems like people don't learn. These guys are 1-2 year fixes who are probably toxic assets by the time they're 30. Spending £50M seems like a poor use of resources.