I agree with you broadly but your analogy is flawed because patches have zero marginal cost (once developed, code can be infinitely duplicated at no additional

I agree with you broadly but your analogy is flawed because patches have zero marginal cost (once developed, code can be infinitely duplicated at no additional cost) whereas vaccines are physical entities and therefore giving one to somebody entails not giving that same item to somebody else. If Microsoft had already developed these patches why not distribute them widely, since it costs nothing to do so and takes nothing away from paying customers?