I came from a 2017 Intel MacBook Pro before my M1 MacBook Air, and a whole host of Intel MacBooks prior to that. Although things weren't always perfect, there was never a consistent and reproducible issue like this with the M1 Macs.This issue isn't new, nor is it relegated to the new M1 Macs. Been having the same exact problem on an 2012 Mac Mini (though not consistently) and now that I've just upgraded to the latest M1 Mac Mini, I'm still experiencing it.
Working around this by powering on the monitor first before the Mac. Annoying.. but I suspect it's a DP compatibility issue
I'm very happy with performance of the M1 in general (other than the Preview app crashing frequently which was not an issue before), but waking up to start work and forgetting that there is a "startup procedure" to getting your gear working can ruin your morning.