Who are 'Man United', in that context? The fans would love him, I'm sure. But the likes of Brailsford and Ratcliffe? They'll (rightly, tbh) want a manager to buy into THEIR global vision for the rebuild of the club - not a hothead who will want things bent to HIS will.
Can't see it for a second, tbh. the whole new INEOS / Ashworth / Brailsford ethos, is about meticulous attention to detail, marginal gains, etc. Not passionate outbursts and impulsive decision making.
Not suggesting its out of the question, but if it happened it could only end badly (and quickly).