Understandable, I was hoping there was some sort of board schematics or even block diagrams to aid in fixing blown up chips and other faults. I most often see failures on the main board and of course that's the part they don't sell you.
While no board schematic there is quite good selection of guides hosted iFixit (Valve links you there from their website so it is the "official" source)
It most often seems to be the power management/charge/USB-C chip, with no particular pattern other than "playing a demanding game". Doesn't seem to matter whether plugged in or on battery, official charger or other USB-C charger or dock. I even had it happen to my own Steam Deck (while playing Minecraft of all things) which I sent into Valve and they replaced.
I haven't been able to investigate it too much but last I looked at the data sheet for that chip it seems like there's no way it should have a hole blown in it unless something was designed wrong.