The basic rule of thumb is for every hour in class, a student should expect do two- three hours of work outside of class. My D is usually right around that mark. So depending on course load, 10-12 hours/day inclusive of attending class seems about right if it’s M-F.
What does worry me for your D is the “bragging about how little sleep they are getting,” not valuing ECs, everyone needing mental health services, and most importantly the word “suffering.” If that’s how your D is feeling, I would definitely encourage her to transfer. That sounds like a recipe for disaster to me.
My D works super hard at school (we saw first hand after pandemic and finishing out a semester at our dining room table) but she has time for meaningful ECs and friendship connections. She typically worked 14 hours days M-F but that was inclusive of her clubs and breaks to chat with friends. Her study groups were all friend based too so they would be working but also socializing. There was a ton of laughter and she has found a good balance. I hope your D will find the same!