Wasn’t the only spare land around the swamp bought by neville who built a hotel?
No.
He just owns the hotel and the the land it's built on.
United have enough land around OT to build a new stadium. The land is leased out to various companies. United get annual revenue from that.
The Glazers don't have the vision or the appetite to fund and to build an arena.(too late now) They would rather bleed United dry from the safety of America.