short answer, because those programs didn’t exist or had lousy bakes compared to xnormal. 🙂
It comes down to the workflow though what needs to be done. xnormal has plethora of settings to tweak. that zelda armor is awesome, and picked up few things from that what i’ll be incorporating my own work flow.
if we look that workflow from different angle, you definetly could do everything inside blender and its a valid way to work too. 🙂
you could also just use the low poly version of the mesh, load it up in substance painter and paint all the details/dents/scars with height/normal layer. export the normal map out, and back in subspainter, then bake rest of the maps for smart materials and finish the thing looking same.
as for jaggies and other error with normal maps, those usually come with the low poly mesh being too low poly and the uv layout is bad for the detail that is being baked on it.
