Yeah. To me it looks like macOS goes so deep into sleep it disconnects the external display. On wake, the system rediscovers the external and resizes the desktop across both displays. With a bunch of apps/windows open, half your apps simultaneously resizing all their windows can peg all CPU cores for a number of seconds.
(It's still way faster than the same set of apps on an Intel Mac laptop, where it could sometimes take on the order of 30 seconds to get to a usable desktop after a long sleep. On Intel Macs it seemed more obvious that the GPU was the bottleneck)
(It's still way faster than the same set of apps on an Intel Mac laptop, where it could sometimes take on the order of 30 seconds to get to a usable desktop after a long sleep. On Intel Macs it seemed more obvious that the GPU was the bottleneck)