The reason there’s a mod for it instead of it being present in the main game is that in reality the devices to do it are either prohibitively large or prohibitively power-hungry. Finding a food packaging plant that has such a device and getting it running is a possibility in the future, but having i.e. a device in the back of your truck to do it doesn’t seem to make sense. Basically lower-tech forms of food preservation scale much much better.
One niche that does make sense is if you find a passive emitter, these are prohibitively expensive to assemble, but if you simply find one, you have an almost-free food preservation solution that just requires you to take food to the irradiation facility.
