I wrote these words August 2, 2020.
I wonder if R5 and R6 are insensitive to DOFBOD (DOF Button Of Death). I coined the term (DOFBOD) myself. It may sound a bit too serious, but I had to come up with something. I created some video posted below for our Polish CPS (don't worry, I included English subtitles), as the saying goes one picture for a thousand words:
Przycisk DOF to przycisk śmierci dla EOS 5DS R oraz najprawdopodobniej również dla modeli (ta sama lokalizacja przycisku): / DOF button is a button of death ...
tinyurl.com
Probably all cameras with same DOF button location (5DS/R, 5D Mark IV, 5D Mark III, 7D Mark II) are affected, definitely 5DS R (which I am currently using, I bought it in May from the gray market) and 5DS (I have used this camera in years 2015-2019, I bought it from an official distribution source in my country).
The solutions to the problem are simple.
1. Before putting the camera in your bag, turn it off with the physical switch. Which of course could be a problem, if you want to have in your bag camera ready to wake up quickly.
Unfortunately, this may not help 1D X Mark III users, by quoting
https://www.optyczne.pl/445.2-Test_aparatu-Canon_EOS-1D_X_Mark_III_Budowa__jakość_wykonania_i_funkcjonalność.html "One of the buttons (the one with the flat surface) is the standard depth-of-field preview, and the other is the M-Fn2 function button. It is worth adding that the pair of buttons intended for the vertical handle remain active, even if the switch mentioned earlier is in the OFF position."
2. Do not put your camera in the size known from the 5d series or bigger in the Lowepro Passport Sling III bag (it's my everyday bag), with replaced interior (I have been using the Ape Case Cubeze (sorry but I don't remember what number) storage bag for many years) as I do.
3. When it comes to currently produced full-frame Canon cameras, buy yourself R, Ra, RP or 6D Mark II.
It's August 3, 2020 and I just got a reply from our Polish CPS:
A button that has no assigned function is still functional, and if pressed prevents the camera from sleeping. This is the correct operation of the equipment.
Thanks to you Canon, it's a pity that you didn't draw the conclusion from the negative lesson that Nikon gave its users well over 17 (sic!) years ago, that is when this post was published
https://www.photo.net/discuss/threads/nikon-n80-eats-batteries.49504/#post-821784