I commute on a MTB and I would be launched over the handle bars if I didn't avoid potholes, kerbs etc. TBH I have to avoid them in the car, and look at the tyres on that.
Shift your weight back to un-weight the front wheel, should have no bother going up or down flights of stairs on an MTB let alone a pot hole or kerb. An MTB can handle a lot more than a car can, just take a look at what Danny MacAskill gets up to.