I would like to propose the following hypothesis.
As Canon updates the software and operation of the image stabilised binoculars, for instance, the 10×42 L seems to have a cut-off function when the binocular is held vertically, the following may occur.
The more sophisticated the software and the electronics, the more sensitive the binocular becomes.
In addition, Canon claims several times to have reduced the power consumption to increase the battery and operational life before having to replace batteries.
This increased sensitivity may be causing the apparent malfunctions.
I don't think that early Canon image stabilised binoculars necessarily had to be stored horizontally, but this may be beneficial nowadays.
In other fields, it seems to me that progress sometimes actually means things get worse unless you are fully aware of how to apply the increased sophistication.
I have little understanding of computers, but I like the Canon image stabilised binocular because it does not require a knowledge of digital technology to use the binocular successfully.
I can also work most cameras, as I have learned to handle them through trial and error, and I don't use any sophisticated functions.
I've seen the results of being able to talk to cars to get them to supposedly do various things. But actually what seems to happen is often a meltdown. Again, increased sophistication actually means going backwards.
I suppose most people seem to embrace new technology at an ever-increasing pace.
When I look at people today in the sunshine, about 80% of them are glued to their digital devices, instead of just enjoying the weather and nature.