because they are lazy and sleep all day ?
or could it be that evolurion is a fairy tale ?
Evolution is a fairy tale?
No, let’s all accept the truth about this one man and his incestuous family, his partner made out of his rib, and that talking snake. Only that can be the truth. No fairy tale, this!
The evolutionist would say that conditions might not favor the larger lion over the smaller ones. In the theory of evolution, species differentiation is the expected result of different conditions and different roles. Big cats eat hooved prey, little cats eat mice and voles.
With changes in conditions, like an ice age or a meteoric catacylism, an adaptation that was favorable in one era becomes an impedement in another. Evolution would not predict or require all animals evolve towards giantism or any other extreme trait, rather the most successful species would be those that balance competing requirements.
Large lions need a lot of prey in order to get enough to eat. You only need to be large if there are large prey animals that can only be brought down by a large predator.
I'm guessing that packs of humans armed with spears and arrows killed off the larger prey animals, and the lions starved. Evidence exists that the same happened in the Americans, with the extinction of large American animals happening about the same time that humans crossed over from Asia.