Why not add code to games that does what what the code in Android did? Its an open standard, the designers can probably do that if they can find the right calls.
There's of course a good reason not to do this - your battery life will go down, maybe the device will overheat, and so on.
Processors in phones are not built to run as fast as possible. They are built to run as fast as possible while giving good battery life, lasting at least as long as the warranty, and not burning holes into your trouser pockets. Samsung could easily build a phone with a processor that is twice as fast. So could Apple. It would just not be a very good phone to own.