Why doesn't the watch have any way of knowing when the wearer is having intercourse?

It would kind of surprise me if this had not been asked before, but why doesn't the Garmin watch have any way of "knowing" when you're having sexual intercourse? 

A few days ago it so happened that a few minutes after starting the "activity" my watch suddenly started buzzing alarms on end about me having an abnormal high heart rate for more than 10min while "idling" (which I was definetly not). I had set it to 110bpm, and yea, I guess that would be a bit too high if one was idling, only that I was not (it is probably quite normal too that one has elevated bpm when being "active" in that kind of way). 

Obviously, I'm aware there are workarounds to prevent this (as I do not think I need to elaborate further when I say that my partner and I both found this mildly irritating, and at first didn'teven realize what was going an until our attention was drawn to my buzzinga wrist), such as setting random bogus activities, but on the flipside I'd like to know if my heart rate spikes too far up during this "sportive activity" (not saying I'm cessarily at risk, but if my heart rate spiked to 190 it might still be nice to know). It also seems a bit prude, that you can't choose "sex" from the list, I have settled for "cardio" now, as this seems to most accurately represent what I'm doing from the list of selectablr activities (as opposed to breathwork, gaming or meditation I mean. Or should I use "mixed martial arts"? ). 

On that note.. why is the watch incapable of noticing when their wearer is having sexual intercourse when it literally tracks everything else, and instead sends an idle alarm cause my heart rate spikes for "no reason" while "being idle"? Certainly, it should be possible to implement algorithms to distinguish actual idling from being "active" in "that kind of way", considering it even calculates my respiration from my heart rate.. So when my respiration - while idling - suddenly goes up alongside my bpm for seemingly no reason, and the movement tracker does detect movement....: wouldn't that be something the watch could use to decide NOT to start buzzing on my wrist like a bee hive? . 

I tried to phrase all of this as professional as I possibly could, as I wanted to avoid violate any forum rules . I hope I succeeded, and this is a genuine question / request