I don't know enough about vaccines to dispute what you're saying (though I feel like I have heard contrary data on this), but even if it's only fully effective for 8-9 months, isn't the fact that we had a vaccine that accomplished at least some of its goals safely designed and tested in record time a really cool thing?

Even if it's only effective for 6 months, that's still 6 months of slowing the spread, and conceivably we can extend the efficacy by administering booster shots.