We have already done so, the first production was potentially at a loss if the Phase 3 results were not good. And we have done so for each vaccination effort out there. So there is already a lot of oversupply we may be throwing.
To be clear, I agree that the return on investment of a quick and successful vaccination campaign is so big that it makes sense to aggressively bet on it. But I also think the evidence shows we have bet quite aggressively on it, at least to unprecedented levels.
What I cannot comment on is how much better we could have done, the supply chain and logistics of producing 1 x (world population) for each candidate vaccine in the hopes at least one of them works and we can roll-it out quickly are so ridiculously complicated I don't know how it could have been made to work. I fear I would just be misdirecting my frustration with the current situation and an incomplete understanding of the problem from the comfort of my armchair.