Privacy is only one dimension, of course. While space is cheap, time isn't, so having less data can also mean less data processing (for example, when possible,

Privacy is only one dimension, of course. While space is cheap, time isn't, so having less data can also mean less data processing (for example, when possible, using online algorithms to compute what you really care about instead of logging all the things and then computing what you really want on demand). However... "We might not have an immediate use [...] but we'll ask for it anyway in case it comes in useful later [...] so if we come up with some way to use that data later, we can." That, at least in my experience, is the major motivator. Unless either the ethos changes or stiff penalties instill sufficient fear in the incorrigible opportunism of the the internet tech sector, the fear of missing out will continue to be a major motivator of the lust for data.