In recent Issue 898106 there was a hypothesis that some recent (small) changes to driver bug workarounds had caused an increase in GPU process hangs. This was disproven, but there may be a possibility that the GPU watchdog is not working properly on macOS any more, and correctly detecting suspends and resumes. There have been fairly recent bugs in the GPU watchdog and GPU message pump on other platforms, such as Issue 596190.

We should reconfirm that the watchdog is working as expected. The steps from  Issue 258617  can help verify this.