Mechanical safeties on firearms are not a solution for preventing mishandlnig by children or compromized adults. There is no "good" way to leave a firearm accessible when there's someone in the house who doesn't need to be handlnig it.
Have you seen 5 year olds these days? Most of them can play call of duty and candy crush on mom’s iPhone in the car seat, better than the adults! You don’t think they can figure out how to disengage a safety?