That's also an idea proposed for London City airport. It's prime real estate in a city desperate for more housing, it handles relatively few passengers, causes

That's also an idea proposed for London City airport. It's prime real estate in a city desperate for more housing, it handles relatively few passengers, causes large amounts of pollution and noise problems, and its USP of being so central will be diluted when the faster trains to Heathrow are completed. On top of that, the airport doesn't actually make much money (in terms of £/area). I wonder if it would make sense for an investor to buy the airport, shut it down and sell the land for housing, surely the land is worth £billions for property developers?