AAQ; Limud Torah isn’t limited to abilities. A masmid who spends his whole day learning, every day, and it takes him one full month to master one pasuk in Bereishis — even before getting to Rashi — is just as entitled to dedicate his life to full time Limud Torah as the next masmid who masters a new Mesechta — with Rashi, Tosfos and all the Meforshim — every month.
And both the aforementioned masmidim ‘s Limud Torah are equally effective at protecting every Jew across the world from any harm.