Her showing up to those states would not have made black and progressive voters like her and she got about as much of the moderate democrat vote that a democrat can hope to get,more than she actually needed.
Hillary's campaign can be summed up as:
"trump sucks and his supporters suck too"
If she spent as much time talking about jobs, economy, trade, etc... she could have won the 300,000 - 400,000 votes that were swung to trump or dumped on Stein. She had no campaign plan while trump screamed every magic phrase voters wanted to hear.