DCRainMaker pretty much debunked Whoop due to its poor accuracy. Maybe some potential if the sensor were accurate.
I track my sleep two ways - one using my Suunto watch and another via the Sleep Cycle app on the phone. Like others have said, it’s usually total hours of sleep that tells a useful story over time. For me, multiple days less than six hours of sleep equates to difficult workouts and injury. My watch is older so it doesn’t give HRV or RHR. I can see how those would be valuable.