Have you even read the standards? You're effectively saying everyone who passed them shouldn't dive unsupervised. Ludicrous.
I feel you're conflating the standards (which are fine, IMO) and instructors not teaching to the standards.
I have read them. The standards have been dumbed down. Several "specialties" have no business being a "specialty" course. Buoyancy, Equipment Specialist, heck even Navigation should be covered to a higher level.
No instructor should be frantically trying to check off boxes before they run out of pool time. No student should be desperately trying to clear their mask so the class can move on to another skill.
Any certified diver who is who is qualified to dive without being monitored by a divemaster or instructor should be confident they can plan a dive, make a sensible go/no go decision, and lead that dive.
There have been threads on here asking that very question, do you feel your course prepared you to dive.
It's no wonder that there are so many idiots on the road. The standard to obtain a drivers license are pretty weak in most jurisdictions.
We have succeeded at doing the same thing for scuba. A few multiple choice questions, cover the most basic skills to the minimum standard or at least close enough, and hand that person a certificate to do... anything. Maybe tomorrow they will dive from a boat even though they've never done it before. Perhaps a night dive. Or gosh darn it, deploying an smb would be real handy right about now. I just wish my instructor demoed that more than once in the pool. Hmm, if only we had discussed gas planning or calculated our RMV just once.
Perhaps if Ms. Mills had covered "dive decision making" or some sort of risk mitigation topic during her open water course, she may have said "this dive is dumb, I'm not doing it today."
Had she simply been an open water student, then the failures would rest solely on the instructor and her general common sense as a student.
Lienna was a certified diver, and any competent diver should have noticed that the risks and uncertainties were stacking up against them, or at least that their instructor was full of it.
I'm not sure how long you've been diving, but think back to what you knew and how confident you were on dive number 7 or 8. What else do you wish you knew back then, what did you have to learn the hard way.
There have also been many posts here pointing out the number of dumb things they've seen divers do, or have done themselves. Is it because these people are fools, or were they run through a program as fast as possible, provided the minimum knowledge to get by, given too little time to practice a skill, and handed a certificate before they were ready.