Justifications for why there are no mentions of Nirodha Samapatti in the earliest stratum of the Pali canon?

As the title states, there are no explicit references to Nirodha Samapatti in what is widely considered to be the earliest stratum of the Pali canon (which includes texts such as the Sutta Nipata, Atthakavagga, Parayanavagga, Itivuttaka, Udana). I'm interested to hear from those who consider Nirodha Samapatti to be a canonical teaching of the Buddha - why do you think there are no references to this attainment in the aforementioned texts?