Yes, it's glorified impulsiveness. Quitting is one solution. But it isn't the only one.
The study itself is better reading. It finds "people may be excessively cautious when facing life-changing choices" while conceding "that the research subjects who chose to participate in the study are far from representative...as there may be sample selection in which coin tossers complete the surveys, and responses might not be truthful" [1]. Furthermore, in allowing participants to choose the question they wanted to answer with a coin flip, it selected for questions to which thought had already been devoted.
The conclusion is best interpreted as "if you've thought through a big decision and remain unsure, there is preliminary evidence that you might want to risk going for it." Not that the moment a trace of dissatisfaction crosses your mind, you should give up.
I'd wager it comes down to taking control of your life. Even if life is "harder" by most measures after the change, knowing that you have the ability to make a change without the world ending is powerful. A new job, new year, new relationship, etc, etc is a chance to reset and do things "better" this time around.
Even if this particular change doesn't work out for the better, it changes your mindset.