such an important point here. The benefits of exercise are maximum when you start from a sedentary life. You will hit plateau at some point and then one has to re-think the plan.
I am doubtful that just 10 min exercise over a few years will get you in a better shape.
Another factor greatly ignored is HRV as key indicator of recovery and response to an exercise. Andrew Flatt (1) is a researcher and has been studying his cardio fitness through HRV for over 10 years. His observation is 10 sec high intensity + 50 sec break in between for 10 minutes improved his hrv. He also thinks 15000 steps contribute to better HRV as good as athlete level.
While there are plenty of questions about 10k steps, what if 15k steps do the trick?
In general, I think since HRV and VO2 max are trackable using hand-held and would be best parameters to track usefulness of an exercise over time. It is always likely that an exercise works at some point and doesn't at other. Possibly because you are more fit now or you have other life stresses dragging you down.
In my experience, a lot of these studies are not reproducible. Because every person is different and context is different too. Genetics add another layer to this. Best is to keep track of your own parameters and try things out.
References:
[1] https://hrvtraining.com/