Ever since chip manufacturers transitioned to variable frequency clocks, they've been inclined to put the overclocking headroom into the boost clock. That's really more beneficial to a larger swath of users instead of keeping that untapped performance only available to geeks.
Generally speaking it has also encouraged engineers to devise better process and thread management which is really important for today's SoCs that have a combination of performance and efficiency cores (like your typical smartphone).
Joe Consumer really doesn't have the time, inclination or expertise to diddle around with power settings. If some soccer mom wants to use her brand new Samsung Galaxy at its peak efficiency, it makes more sense for the performance curves to be set by people who have advanced degrees in engineering, mathematics, physics, etc. from the best engineering schools on the planet rather than fuss with this yourself. Same with computers.