Because Moderna has obtained approval and have booked a billion doses for sale, and if this thing really is an endemic, they'll be making money for a long time. They announced today that the vaccine is still good for the current mutations that have been tested. I'm sure it will be a game over time, much like the flu vaccine, but if you look at what they are doing, the whole mRNA vaccine technology is likely to change the way every vaccine is created.
Also realize that we are already up some 400% on COVID speculation.