I would allow my kids to wear diapers.
They would not be potty trained and would go poop and pee in their diapers so they would need a good absorbent diaper.
Diapers are much better than pull ups.
They would never be out of diapers from birth until they turn at least 18 and move out.
They may want to wear diapers then as well but if not that is okay.