The benefit of smaller nodes is lower electricity usage per calculation.support it.
If an IC will sell in 100 millions there is same (marginal) benefit to go for small node ( like slightly smaller mobile phone : D ) , but I seriously doubt that there will be any base-station controller on sub 22nm node.
Smartphones have limited battery capacity.
So a smaller process node means the smartphone lasts longer before it runs out of battery.
With datacentres, it's the lower operating costs of electricity and the associated cooling costs. It costs less money to do the same work with a smaller node