Running into the same issue (instant reboot) with my FW13 7840U 64GB RAM, journalctl has no indication of a crash. Running openSUSE Tumbleweed using the latest firmware/bios.
I’m curious if this is load-dependent. I was having this issue on Gnome frequently until I disabled file indexing. However, with KDE I get it more often (even with file indexing turned off) which has caused me to start looking for solutions.
I assume it’s also worth noting that I’m almost always running my laptop docked to a Caldigit TB4 with a high refresh rate 4k display connected, so obviously there’s a bit more stress involved than with the laptop undocked.