If the UK had ordinary 'it's expensive to build things in built up areas' costs and outcomes I think the 'that's just the knowledge economy for ya' take would be more compelling. How could this sort of behavior *not* be reducing investment?

I suppose, because business sector investment as % of GDP has been falling since the late 1980s, & the decline is driven by manufacturing investment & then by ICT investment. and the UK is the most deindustrialised of the big rich countries, in terms of manufacturing value added as % of GDP