It was recently announced that the City of London -- the historic town center and primary CBD of the region -- is aiming to create at least 1,500 new residential units in the Square Mile by 2030. Part of its strategy is to convert disused office buildings into residential. Currently, the City has about 7,850 residences, which is a drop in the bucket and whole lot smaller than its 19th century population of 125,000.
Tony Travers, director of LSE London, is quoted in FT saying that the City is really facing "twin challenges." You've got Brexit, which caused prime office cap rate rates to stagnate in the UK, and you've now got the whole work from home thing. Nobody really knows how this latter piece will fully shake out when it's all said and done, but we shouldn't forget the power of agglomeration economies. It's what powers cities.