I’ve read somewhere it is because conpressor nozzke has to be made thinner/fragiler for the better efficiency. Other comments say it’s because old refrigerants were better but more “dangerous”. Maybe both.

Is this from Warhammer?

Old fridges never die. Modern fridges are more efficient but more break-y, can’t have both.

Yeah, OOM not being aggressive enough (i.e. not triggering at all) is an age old issue. There’s earlyoom or nohang for this, further ressources in the description.