Mountain bikes over $2000 are really the top end bikes. There’s a wide variety of specialist bikes including electric mountain bikes and some hard core downhill and trick mountain bikes. These bikes are very heavy duty yet are generally very light being made of “space age” materials such as carbon fiber and other composite and lightweight, high strength materials.
Given the terrain some of the more extreme riders go, gear failure is NOT an option so having top quality and highest performing mountain bikes is essentially to get your thrills and get back safely without a broken bike or body !