Yeah, if he would be castrated. But then he'd lost his mane.
Sterilized means only that the Seminal leader is cut, so he cant produce any cubs.
A good thing, because there are too many zoo-mix-lions.
But the P. l. leo (Barbary) are of doubtful origin, and probably not pure, which leaves the Asians and the likely inbred White krugeri of WMSP/Broxbourne/Heythrop. And a whole stack of zoo lions.
Where is the source for this information? Are you sure they are more pure than either of the cats you mention? As far as I was aware, they may be genetically distinct in some ways from the generic african lions, but skulls and other items from long-dead known barbary lions have shown the current living animals claimed to be barbaries as quite different.