Most of East Asian Buddhism is Mahayana. The basics of the Mahayana path are the six perfections.
Much of late East Asian Buddhism characterizes the "three vehicles" into three main doctrinal focuses:
1. Sravakayana = four noble truths
2. Pratyekabuddhayana = (twelve links of) dependent origination
3. Mahayana = six perfections (etc.)
The connections are clear when we consider that in this type of doxography, the "sravakayana" is largely Abhidharma based, which establishes the four aryan truths as it's core. Eg. see the whole layout of the Abhidharmakosa. Also, the common reading of "pratyeka" as derived from "pratyaya" and not "prati-eka", relates the Pratyekabuddhayana to dependent origination. The Mahayana sutras themselves state clearly that the perfections are the practice of the Bodhisattvas.
Moreover, these later traditions would assert that a bodhisattva "should not attain the nirvana of the sravakas", etc., which is another implicit move away from emphasis on the four noble truths.
Moreover, as East Asian Buddhism progressed into the late Tang and Song, and thereafter, each of the various schools had their own special emphasis. For instance, Chan had it's "direct pointing", the Pureland school it's "recitation of Amitabha", and so forth. In these systems, the four noble truths were very briefly touched on, and glossed as "sravakayana" / "hinayana" teachings, so relatively not important.
In the modern period, due to various influences, mainly the global village, there may be a greater move towards appreciation of the four noble truths within some Buddhist communities in East Asia. This is by no means universal, however.
Now, given that this is a Theravada Forum, no doubt a few people will have some serious problems with all this. Whatever the case, this is basically the situation in East Asian Buddhism. I don't think that these traditions are any the less "Buddhist" as a result. And, before commenting either way, it is first preferable to actually have some understanding of these traditions, rather than engaging in un-informed criticism.
End of pre-emptive note.
My recently moved Blog
, containing some of my writings on the Buddha Dhamma, as well as a number of translations from classical Buddhist texts and modern authors, liturgy, etc.: Huifeng's Prajnacara Blog