I wouldn't mind this (a ring is another option), but 1) you can disable notifications, which I tend to do and 2) the problem is that all independent experiments keep claiming that almost everything is inaccurate out there, and Apple Watch is one of the few surprisingly accurate ones, as compared to real medical equipment.

> Best of all no advertisements pinging me every few hours.

Skill issue.

The first thing anyone should do when they get a smart watch is disable all notifications. It's so easy to do and it makes the experience so much better. It's completely backwards that notifications are opt out. Sadly, I've never seen anyone change their defaults.