So that some employees at Google can have easier time managing an issue(not disclosing the reason for account restrictions probably makes the scammers life harder too
Yet, while this is often the cited reason, it is simply not true.
There is no way on Earth, that scammers don't find out about such restrictions trivially, easily. So all this really does, is inconvenience the honest, and do zip, zero, nada to hassle the miscreants.
edit: more thought here, likely this is just an excuse, to not properly train reps, or to not deal with the issue at all.
It is the equiv of "think of the children!", but corp speak instead of politi speak. "Sorry for the bad service, security issue!"