People still do stuff with death rates approaching 25%... Like climbing Mt Kangchenjunga, or K2. the 10% of CT low berths is a disincentive, but given a large enough population and/or a callous enough government, it'll be used. Heck, people ship themselves in cargo containers (and die in the attempts) to illegally enter the US.
A naval or civilian low berth at TL 15 should be a pretty safe place. But illegal low berth transport is a slightly different topic and stat.