Because there isn't much that is actionable with sleep tracking. You can lose weight if you have sleep apnea, and anecdotally people claim that not drinking helps, but you don't need a watch to tell you that. With blood pressure, you get on losartan and see the results immediately.

I don’t see how there is nothing actionable from sleep tracking.

If I have a week of bad sleep scores I don’t go for a long run on the weekend. I don’t indulge in things I would otherwise do, and I make an effort to get off a screen and to bed earlier until I get a solid 8 hours of sleep