"Pizza-box-sized" was a placeholder. The Starlink antenna ("Dishy") has a diameter of 59cm https://i.imgur.com/ULwOGxs.jpg
More people are willing to buy a phone and a phone plan (Facebook was even willing to subsidize the plan in India with Internet.org) than buying a phone, a phone plan, an antenna and a StarLink plan. That's even more true for people who aren't internet users yet.
I don’t know what kind of barbaric society you hail from, but here in civilization 12” is a small pizza. ;-)
That's quite a bit bigger than even a large pizza.
I measured out 59cm on a measuring tape and compared it to my refrigerator, and that's much larger than any pizza I have ever seen.