M2 Macbook Air won't turn on

Completely dead and fully charged MacbookAir 2022 M2 Ventura 13.2.1.

My assumptions are this is not* a software issue, because Disk Utility First Aid finds nothing.

Nor is it a hardware issue with the machine itself, because hardware diagnostics finds nothing.

But the key point is that the laptop is plugged into the Apple Studio display, which has no power off button (!) and so disconnecting the machine from the display means either sleeping, powering off or simply ripping the cable out of the Mac live.

When the machine dies, it cannot* be turned back on at all. No button turns it on. Closing and opening the lid does nothing. This time it powered on when I plugged in the Studio thunderbolt cable then yanked it out and... suddenly it chimes and loads. The last time it was dead for an hour then suddenly chimed on when I opened the lid, after opening and closing the lid multiple times. And then it works like nothing is wrong for a month, until it decides to torture me again. I'm thinking it's the Studio Display somehow.