This has a rather seductive appeal. Largely because the 16-18 age group is notoriously difficult to penalise in any significant way. So why not punish them in a way that hurts, so that they might perhaps realize that if they do not take responsibility for themselves then there will be consequences.
The difficulty with the idea, it seems to me, is in using an unrelated activity...driving... to address another issue altogether...truancy.
The problem then is that we think we have addressed the issue, but the truth is that we have not done anything at all to address the root cause. We do not even name the root cause instead all we do is deflect it.
If, for example, the cause of truancy is bullying at school; or drug addiction; or poor parenting or (God forbid) the failure of the school to seriously engage non-conforming adolescents ...then how would delaying the driving licence actually address that issue.
Further, it would seem to me, that it is a very bad principle to do something draconian because it is notoriously difficult to do something meaningful.
Attractive, seductive..yes. But quite wrong headed.