Piketty's 'Capital in the 21st century' raised the claim that the returns on capital are starting to outweight the increases in productivity. Is the diminishing

Piketty's 'Capital in the 21st century' raised the claim that the returns on capital are starting to outweight the increases in productivity. Is the diminishing of office space actually a side-effect of this? If the penny in investments gives better returns than the penny spent in worker productivity then open plan pens - excuse me, offices, would actually make sense.