Mountain bikes do not require roads or flat paths; they work fine on trails (hence the name "mountain bike"), which have existed since large animals evolved.
However, mountain bikes arguably require even more technologies than other bicycles, especially for suspension and brakes (MTBs pioneered the use of disc brakes on bicycles).
However, mountain bikes arguably require even more technologies than other bicycles, especially for suspension and brakes (MTBs pioneered the use of disc brakes on bicycles).