This is bs. There are loads of football fans, including plenty here, who love that thrill of online pile-ons, that will continue to deride him whether he stays here or goes elsewhere. There's a truckload of people to laugh at him and say 'that's your level' if he moves to a mid-table or relegation-scrapping club.
Is he more the 'wet lettuce' for wanting to stay and fight for his place at the biggest club in the country, rather than move somewhere like West Ham? I'd imagine it's way more mentally challenging for him to remain at United, given the guy's had bomb threats to house.