Yes, setting limits for kids is better than locking everything down. Just because your house is completely child-proofed, it doesn't mean every one of your friends and family members' houses will be.
Teach them hot (stove), cold (fridge) and yucky (playing in the toilet) and they will be better off. Safety gates at the top and bottom of stairwells is a good idea, and outlet covers (but they should still be taught to not touch the outlets or stick things in them). I had the basic safety measures in place when my two children were little, and there was no lock on the fridge, stove or toilet seat.
How can you potty train a child if they can't get to the toilet? What message does that send to them? "You need use this, but it's locked so your little brother can't play in it."
My advice to new parents: teach safety...don't rely on all the little gadgets available to do it for you. And most of all, actually pay attention to what your kids are doing. If they're quiet, go see what they're up to.