I confess to you that it is very hard for me to grasp that a serious company in this industry would have such a practice or SOP. There is so much information and info on best practices on that matter that it just doesn't make sense to me, particularly as it relates to both passenger health/risk and crew health/risk.
So there you are; a seasoned captain, perhaps via a few airlines and perhaps even military. You've spent your whole life training and practicing Emergency Descents and Pressurisation problems. They've all been to the common standard of descent without unnecessary delay. I didn't say rush.
Now you end up at an airline with this as an SOP, and the worse happens. What are you going to do? It is your own life at stake + all the pax. You have more than enough O2, but they............Could this be the time to enforce "deviation from SOP for flight safety reasons SOP"?