[davidmanze]

although personally I don't care...but A7siii does overheat and sometimes faster than R5
https://petapixel.com/2020/07/30/sony-a7...es-report/

 In this "one case scenario" in Florida in full sunshine at the height of summer the A7SIII overheated a minute or two faster than the R5 ........ although the R5 had to be restarted again due to the 29 min shooting limit to achieve those few minutes ..... (so in any case it wasn't continuous shooting)

 This "wasn't" because the A7SIII's sensor was causing the overheating so much as the heat of the sun was conducted to the sensor by the passive cooling system which was "adding" to the normal heat created by the sensor itself...... 
.... this would not have happened had any form of shade would have been provided !!...


OTOH ...... "in shade or not" the R5 "cannot get the heat out to the outside world" and as a result the time for the camera to cool down is huge ..... with people observing "very long cooling down periods" before the camera can shoot again and even then, for short durations before it heats back up again.
 
This has been confirmed by those who have attempted to cool the R5's exterior with ice-packs placed on the body .... as well as fans, "it makes little difference" ........ that cooling just doesn't reach the sensor which lives insulated remaining hot.
 
  So this minuscule two minute victory for the R5 is rather hollow and pretty much ends there!