Steel walls are impervious to fire, termites, rot, splitting, and any other number of hazards which can befall lumber. They don’t burn like wood and are lightweight and easy to cut and fasten. The factory-punched holes eliminate drilling for the installation of wiring and plumbing, which speeds along those tasks.
Most walls in remodeling projects are non load-bearing, meaning they don’t help support the weight of the house. If you need to build a load-bearing wall, make sure your metal studs are rated for that use.