I think in the English speaking world (and Japan as well in my experienced) there is a notable favouritism for the Theravada Pali canon when discussing Early Buddhism. The idea is that it is most representative of the Buddha's original teachings, life story and the development of the sangha.
However, there is evidence to suggest this might not be the case. The Mahāsāṃghika scriptures and Vinaya might be better representative of said details. Take for example the following point:
(Bart Dessein in "The First Turning of the Wheel of the Doctrine: Sar and Maha Controversy" in Handbook of Oriental Studies The Spread of Buddhism, edited by Ann Heirman and Stephan Peter Bumbacher (Leiden: Brill, 2007), 15.)“The Mahāsāṃghikas were involved in the first division of the Buddhist community in the second century after the demise of the Buddha, that is, the schism between the Mahāsāṃghikas and the Sthaviravādins. This schism was most likely invoked by the expansion of the root Vinaya text by the future Sthaviravādins, an expansion that was not accepted by the later Mahāsāṃghikas.”
This isn't specifically suggesting the Sthaviravādins simply made up material and wanted to add it (though to some extent that might have been a possibility, which the early Mahāsāṃghikas were concerned about). There is also the account of Devadatta, which in the Mahāsāṃghika school differed considerably. He is simply seen as a virtuous monk. The Japanese scholar Dr. Nakamura Hajime was of the opinion, supported by numerous others incidentally, that the villainous stories about Devadatta were simply later fabrications.
This begs the question of what else on the Sthaviravāda side of the early canon was later fabrications. For example, did the Buddha really say that the Dhamma's longevity in the world would fall into demise five hundred years earlier for having admitted nuns? This is something Dr. Jan Nattier in her work Once Upon a Future Time Studies in a Buddhist Prophecy of Decline discusses. Essentially, this teaching is found in the canons of the Sarvāstivādin, Mahīśāsaka, Dharmaguptaka, Theravādin and Haimavātas schools, all of which belong to the Sthaviravāda branch of early Buddhism, though it is not found in the known canon of any school belonging to the Mahāsāṃghika branch. This quite possibly demonstrates a later fabrication, which raises some concern about using the Sthaviravāda canon as a gauge for authenticity concerning early Buddhism.
Consequently, if it could be demonstrated that the Mahāsāṃghika canon, largely preserved only in Chinese nowadays admittedly, is better representative of early Buddhist history, would this not render some contemporary Theravada claims on best representing early Buddhism as somewhat baseless?
Moreover, could this possibly have an influence on contemporary Śrāvakayāna Buddhology in the sense that Mahāsāṃghika conception of the Buddha, i.e., transcendental and supramundane, could be better appreciated and even adopted? Their conception of the Buddha was the precursor for the later Mahāyāna vision of the Buddha, but nevertheless it was based on pre-Mahāyāna literature just as legitimate, if not more than, the Sthaviravāda Nikāyas. It just used a clearly different interpretative approach.
Venerable Guang Xing in his work The Concept of the Buddha explains,
So, really what I am suggesting is that in a Śrāvakayāna context the Mahāsāṃghika scriptures and even ideas might be adopted in light of the fact they perhaps better represent early Buddhism. Some of material in the Pali canon which can safely be regarded as later additions (such as the purported account of the Buddha saying the Dhamma would demise five-hundred years earlier for having admitted nuns) might also be set aside as illegitimate. On a perhaps more volatile note, some of Theravada could possibly enjoy a more transcendental vision of the Buddha, as the Mahāsāṃghikas clearly did, without detaching from its Nikāya roots.The Mahāsāṃghikas’ religious philosophy was based more on faith than on reason, and accepted whatever was said by the Buddha or, more precisely, whatever was taught in the Nikāyas and the Āgamas. As a result, they developed the concept of a transcendental (lokottara) Buddha based on the superhuman qualities of the Buddha, as discussed in Chapter 1 above. Two aspects of the Mahāsāṃghikas’ concept of the Buddha can be identified: the true Buddha who is omniscient and omnipotent, and the manifested forms through which he liberates sentient beings with skilful means. Shakyamuni was considered but one of these forms. The true Buddha supports the manifested forms that can appear in the worlds of the ten directions. In Mahayana Buddhism, the former aspect – the true Buddha – was developed and divided into the concept of the dharmakāya and the concept of the sambhogakāya; the latter aspect – the manifested forms – was developed into the concept of nirmaṇakāya. Thus, the Mahāsāṃghikas are the originators of the idea of the nirmaṇakāya, and the manifested forms can have many embodiments. Furthermore, they also introduced the theory of numerous Buddhas existing in other worlds.