sleeping apps

I find it quite curious how much data collection happens nowadays through an assortment of devices. My sister tracks her run times on her watch, my dad tracks his sleep quality via a watch, and I track my habits on my phone. More interestingly, I’m curious on what kind of data collection occurs when we are not aware. In the case of sleep, the app Sleep Cycle can record and capture the sounds you make when you sleep, including but not limited to sleep talking, coughing, and snoring. I wonder where the line is with capturing data and privacy is, give the latest emphasis on data with the surge of developments in the AI/ML space. What other info can be captured from us when we are unconscious and what does that say about us other than you might be at risk for sleep apnea?