I think they were referring to RAM or storage space rather than human fatigue or mental effort, although I'm not a native English speaker so I may be misinterpreting.

Indeed, there are many low-end smartphones that run out of storage space after one or two years even without installing anything, just with the automatic updates of the preinstalled apps (Facebook is a major offender here, why does their app grow more and more?). Being forced to install an app to use a service when you are in this situation is highly frustrating.