Sincerely, it's great to see an observational study get published in NEJM. It's a pretty sophisticated analysis, and the VA has certain advantages wrt the data they collect. The limitations of an observational study, the constraints on generalizability, and the very modest absolute risk reduction have been discussed more than adequately up thread. But just to amplify the generalizability issue, mean age 71 years, over 90% male, obese on average. The results (esp some of the data in the supp appendix) strongly reinforce risk-based recommendations (age, comorbidities, etc.) rather than universal recommendations that include children, adolescents, and young healthy adults.
It's amazing that instead of reviewing rounds of results from RCTs with each subsequent booster release we are digesting tweets related VA observational studies. Hopefully the new FDA guidance incentivizes more of that kinda work.