Good buoyancy control is a must for every diver. I agree that new divers could have bad buoyancy control. Divers improve buoyancy control with dives, following the example of divers with more experience or having the attitude to improve the skills with every dive and learning from their own mistakes.
It´s important that in the OWD course the instructors not only try their best to teach buoyancy within the short time of the course, but also emphasize the importance of good buoyancy, so that the new diver understands the need of it.
Normally new divers rent gear. Every new dive is a test for buoyancy. Unknown wetsuit (jumpsuit, farmer John + shortie, 5mm, 6mm, vest, hood, gloves, etc), BCD, weight with no marks (if they are 4 pounds or 2 kilograms could make a difference). All this make proper weighting for those new divers a nightmare, if they care.
Yes, mastering every skill is a journey, not a destination. That´s why this PPB course sounds to me not good. It´s a shortcut, ok, but there should be no shortcut. The PADI OWD course should have one more lesson related to buoyancy.
My SSI instructor emphasized a lot, really a lot about buoyancy. We had a pool practice related to buoyancy. During the check-out dives we all had to make a proper weighting test in every 5 check-out dives. After every check-out day (in fact we did 6 dives in 3 days) we were sitting together after dinner discussing every aspect of the day and buoyancy was always a point of discussion.
Perhaps I was lucky with the course I did. That´s why this PPB course makes me feel that PADI is dividing the courses and teaching less in each so as divers need to take more courses.