There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
As for whether other species of cats are yet to undergo a behavioral change towards making coalitions, I would say we should not overlook not other more basic reasons why they live more solitary live - availability of food sources. African plains with plentiful ungulates (still) can sustain bigger groups of predators, no matter how seasonal and unconsistent that source might be. Other cat species living in different enviroments might not have the same density of food available (ignoring the habitat loss and human proximity capable of having an impact), I would say a jungle or nothern forest can't sustain the same density of large herbivores (interesting point brings the articificial existence of liger in captivity, which suggest that lioness posses a growth inhibitor that limits the size they can reach, I guess them being as big as males would be detrimental nutrition demand wise in a group environment, regardless of social dynamics impact).
Plus lions face a tough competition in the form of clans of hyenas that might become serious threat when outnumbering lone individuals or groups too small. Unlike cheetahs or leopards with their adaptation, lions as apex predators mostly compete through power and strenght. Dholes or wolves elsewhere are hardly comparable.