As for the call today - remember you are their safe venting place, the face they can’t or won’t show to detailers or classmates.
They will alternately love and hate USNA during their 4 years there. You do not have to solve any of their problems today. Express confidence they can handle it, ask them how they plan to tackle Problem X if something specific is mentioned. If it’s just general lamenting, turn on the soothing “I can’t imagine how tough that is, can’t wait to see you on PPW and get you off the Yard and hear all about it.” Ask them if there is anything they want you to bring. Be supportive and loving, and prepare for your DS or DD to not sound quite like themselves, because they might be hoarse or rattled or evolving.
If they say words that shake you, ask if they think they can get through until PPW or just the end of PS, and re-evaluate, take it a day at a time, or even a few hours. I think every USNA grad who posts here had those days where they just wanted to walk out the gate and be done with the place. I had the same feelings at OCS, thinking “what have I done, I hate this BS.”
USNA has been doing this a long time. There is a phalanx of hand-selected officers, senior enlisted leaders, mid detailers and recent grads wearing thrmselves out looking after the plebes, with Chaplains and corpsmen right there.