Mostly in agreement - I would note that the Lancet article gives a few arguments with citations as to why the vaccine efficacy decreases might be statistical ar

Mostly in agreement - I would note that the Lancet article gives a few arguments with citations as to why the vaccine efficacy decreases might be statistical artifacts, and so I think you may be a little over-confident on your bullet there. But I agree that there is data on both sides, and strongly agree with your general approach of accounting for the possibility that vaccine efficacy could be waning in your risk model and updating behavior accordingly.