I'm having the exact problem you're having in my population has grown over 150, now it crushed SO f**king often. It's driving me crazy and don't even wanna keep playing anymore. Have raised this with Fallout shelter's support.
Don't know what they'll say.
According to other guys here, what they have done is to send the useless ones to the wasteland and leave them be.
However, doesn't think that's the way to solve the crushing problem.