Keeping yourself busy is one of the best ways for an addict to distract themselves from gambling. They can find a hobby that they enjoy, or do work, or do other activities that keep their attention away from gambling. Because the problem that gamblers often face is that the urge to gamble arises when they are not doing anything
You're right being busy with something can actually keep you from gambling abit but not necessarily on a very solid ground base, cause at this point little things can intice the gambler to keep gambling but I think having indulge oneself to another hobby could also remedy the gambling addiction rate of the person, cause instead of gambling they find themselves doing another thing that brings fun to them.
Everything comes back to intention in the end because even if we are looking for busyness for other things when we do not have the intention to stop or try to minimize so as not to be too aggressive in gambling then in the end everything is the same where no matter how busy when we still cannot eliminate and restrain the desire to gamble then everything will look the same where we will force to gamble even when we are busy.
This possibility always happens so in the end as you said in the end there must be a really strong goal and intention when trying to stop or reduce gambling because it is indeed important to do from the beginning especially this can be a strong basis for us to refrain from gambling like we always do.