The student is forced to stretch and relax in yin yoga, even when the student needs more stability, in yang yoga the student is forced to move through ranges of motion, even when they are not ready.
Cant speak for yang yoga but at the yin yoga classes I’ve taken (at different studios), no one was forced to move in an awkward way. In fact they used body pillows and props o- help with stability. That hardest thing I found was keeping still for 5 minutes (I’m an active mind/can’t sit still kind of girl).
So far it’s been great for focus and has definitely helped me with shallow breathing, also stretching my hips etc. Really never felt forced and I’m not a flexible girl.