Some detterence could be necessary, for sure Morocco have not the econmic Power to counter Spains Military Power 1:1 ! There should be a minimum credible deterrence anyway !How would you know? Have you made a threat analysis for Morocco to come up with these magic numbers? At most they need to face off Algerian airforce and that is it for now. They can not and will not want to tangle with Spain for the foreseeable future for various reasons.
It is more important for them to focus on growth & development instead of armament. Not everyone thinks like you, nor do they need to.