Yes, I agree as well. The likelihood of needing to provide O2 is much higher than the likelihood to provide CPR.
Also, as Quero pointed out, time is of the essence when a victim is not breathing (and therefore we assume the heart is also not beating in EFR), and the chance of getting a victim on the boat within the 6 minute window of time where permanent brain damage is done, is quite low.
On the other hand, CPR can and does save lives in all walks of life, including scuba diving. CPR involves AED. As we are taught in EFR training, chest compressions by themselves do not restart the heart because the heart, in the vast majority of cases, must be defibrillated to restart.
This means, of course, that a panicked diver, for example, who is now in a state of near drowning, will more than likely need to be defibrillated when rescued back to the boat. EFR teaches this, and AED is the key element of CPR because chest compressions do not restart the heart.
So, without an AED on board, teaching EFR is pretty much useless in most dive accident scenarios that require CPR. As limbo said, it would be much better to focus on realistic scenarios like providing 02; or requiring dive boats to keep an AED on board if the dive community really believes that CPR is a mandatory training requirement.
If every student must learn CPR (Rescue and above) and all instructors much teach CPR (requirement for OWSI), then something is amiss, because CPR/EFR requires defibrillation "by the book" and without AEDs on board, the EFR training is more of a "money making scheme" than realistic training to save near drowning victims.
I was disappointed to learn this after my completed EFR/Rescue training this week.
Statistically, the likelihood of a near-drowning victim to survive in a scuba accident can be quite low; and in the less likely event that the victim can be rescued and on the boat within 5 minutes or so, AED increases the survival likelihood dramatically.
I feel like the EFR part of the Rescue training was teaching us what to do, in theory, but without AED, we learn the theory without the tools to properly execute what we are taught. Something is amiss in the PADI training program. (No real surprise here, I guess).