That is indeed what the CT rules say. It's even acknowledged in-universe with things like the Low Lottery.
The Low Lottery ... with "winning numbers" that include deaths ... ought to be a byproduct of inadequate Medical-1 (or 2) skill expertise care. This means that the operator is "credit shaving" on crew salaries (the medical staff, specifically) in order to pad their profit margin each month ... something that bean counters and "middle managers" are known to practice on the daily if it means Profits Over People™.
Conversely, with sufficiently resourced Medical-3+ skill expertise care ... the "winning numbers" for the Low Lottery ought to be "zero" every time, except when there are complicating factors (basically, -DMs in play). The operator of the craft has to "pay more" in crew salary for that higher skill level medical staff, but fewer passengers DIE in transit, raising the reputation of the transport craft as delivering "reliable/reputable" low berth transport services (that more people than is typical survive using).
The difference between these two options, functionally amounts to a "social standing" rating for the craft and operations crew ... which, needless to say, there are no (RAW specific) "rules" for ... but which could add color and flavor to an ongoing campaign of merchant Travellers (for whom reputation is an important, if intangible, commodity!).
Such an interpretation does not PRECLUDE (or prevent) low berths from being "used in an inherently unsafe manner" by those parties of dubious scruples (and insufficient but still "qualified" skill levels) ... but it does mean that parties of "higher than minimum standards" can reap the reputational benefit of being "a cut above" their competitors who deliver better/safer passenger services and experiences (with less frequent casualties from low berth passages).
Arranging things that way means that there is
Emergence in behavior patterns that result from those converging factors, which will have consequences (some doors open while others close) concerning how the TU inter(re)acts with various crews who operate along differing levels of principle, ethics and responsibility.
The "trading game" is one that's easy to learn, but hard to master.
Figuring out that reaching for better levels of Medical skill/expertise in order to minimize low berth casualties and improve overall crew wellness/morale isn't something that the RAW will explicitly "tell you" is true ... but it ought to be something that Players (and Referees) can figure out on their own, if they pay attention and think through the matrix of potentials resulting from choices diligently enough.
It's kind of like how woodworking shop tools CAN be operated safely by skilled craftsman who use best practices ... but those same tools can be operated completely NON-SAFELY by unskilled people who take dangerous shortcuts (that can result in permanent injuries).
There's a reason why "bucket films" of industrial accidents caused by unsafe practices exist ... as a warning to others to not make the same mistakes ... and yet those kinds of accidents and injuries keep happening to the inadequately skilled. It's not the fault of the tools that the operators lack the adequate skills/behaviors/safeguards to prevent injury ... it's the carelessness/lack of skill on the part of the operators that is the source of the hazards.
I figure that the same type of thing ought to be true for low berth technology when used for passenger transport.
Inadequate skill/expertise on the part of the medical staff CAN result in injuries (up to and including DEATH) when people are resuscitated ... but not every crew is going to include/pay for medical staff with a high enough level of skill/expertise to minimize those casualty rates.
At that point, "allowing low berth passengers to DIE when transported" simply becomes another calculation in the profit/loss computation. After all, passengers pay up front for passage ... so if they die in transit, the amoral merchant has already got the (low) passenger's money ... who cares if they don't survive the trip?

It's not like the merchant is being half up front/half upon survival to the destination ... right?
Needless to say, this kind of "low death profiteering" can lead to some very
DARK PLACES when moral fiber is thin (to non-existent) and Money Is All That Matters™ to the (death) merchant class.
Just because things CAN BE THAT WAY ... doesn't ipso facto mean that things HAVE TO BE THAT WAY.

Allowing things to be that way is a CHOICE ... not a REQUIREMENT.
For some, it's a Choice that they'll make eagerly/willingly (because: money!

) ... while for others, it's a Choice that is best avoided ... even though the temptation to Make That Choice will always be present, waiting for an opportunity ...
And yes, I'm talking about Moral Character and Ethics here ... something that you won't find spelled out in RAW, but something that Players (and Referees) shouldn't "toss out the airlock" just because it isn't enumerated in RAW as something that you Have To Do (or there will be consequences). Some things ... don't need rules ... in order to be self-evident, once presented and laid before the assembled.
