Изменено (KPM): 7/22/2017 7:03:32 AMBased on the volume of comments both here and on the @BungieHelp Twitter feed it's definitely not an isolated incident and not even limited to this game it seems! My best guess is that some PS4 Pro hardware may be slightly more susceptible than others when performing specific computationally or graphically intensive operations and the D2 Beta (along with other titles) may just push the GPU a little too hard, just enough to cause a fatal system error. I've seen this kind of instability under load on some PC games running on custom overclocked hardware that hasn't been properly 'burn in' tested. Sony may need to consider a firmware update (especially in warmer countries!) that clocks some components down to make the overall system more stable when running specific software with GPU at 100% utilisation.
Just to add that just because some GPU intensive games play perfectly fine for hours on end does not guarantee that all hardware is equal, clearly something separates some vanilla PS4 Pro consoles in such a way as to cause fatal system errors but it is still perfectly possible (and I'm really hoping!) that this is purely a software only defect.