Except the Stargate also dematerializes you. Also there's no way of guaranteeing that the gate on the other end is open and there's apparently no safety protocols to ensure that it is so you could open the gate and then step through and just die.

Oh you know it could be underwater.

Or in space.

Or around a black hole in which case you die even if you don't enter.

Really they're actually quite dangerous technology and definitely not safe.

Also sometimes they accidentally time travel you