Alternatively, and depending on the severity, they can recognize they've hired a bad (apple|fit) and separate, possibly update the hiring process, and move on.
While adding in new technologies isn't always a bad thing, having nothing but a desire to do so is classical Resume-Driven-Development. If your firm is in a business position such that having all the latest, greatest tools is a good thing (hard to imagine industries in which this is an unqualified good) then keep on trucking. Otherwise you may find yourself needing to have adult conversations with $RDD_DEV about just what it is that makes the business money, in light of technical decisions that cost additional time, have larger TCO, and so on.
While adding in new technologies isn't always a bad thing, having nothing but a desire to do so is classical Resume-Driven-Development. If your firm is in a business position such that having all the latest, greatest tools is a good thing (hard to imagine industries in which this is an unqualified good) then keep on trucking. Otherwise you may find yourself needing to have adult conversations with $RDD_DEV about just what it is that makes the business money, in light of technical decisions that cost additional time, have larger TCO, and so on.