Dr Tony may be making valid comments about this sutra, but it does not mean that this sutra is being treated as the definitive sutra by the majority of people in Mahayana and Vajrayana Buddhism, however there are certainly a handful of followers that hold such Atman/eternalist view that is no different from the Hindu's Advaita Vedanta.
I wrote last year:
Now recently I was discussing with Geoff (online jnana, nyana, etc) and he mentioned: "The "Mahāyāna" is a mixed bag, and has meant different things to different people at different times. I have faith that by practicing the perfections one can realize buddhahood. And this isn't unique to the Mahāyāna. The Theravāda also has teachings on the bodhisatta vehicle."
I can't agree more with this particularly the first sentence.
Mahayana means different things to different people, simply because it is not one particular teaching taught by one person. It is not even from the historical Buddha. Rather, it is a collection of teachings from so many people with different background, situation, understandings, under different circumstances or periods of doctrinal developments etc etc.
Some of those scriptures may be attributed to Buddha, but even those scriptures are not exactly by the historical Buddha (as modern scholarship will tell you) but are composed by many unknown authors writing them - perhaps a visionary account of their teachings, or more likely than not as Malcolm said - "...Even though Shakyamuni Buddha certainly never actually taught Mahayana, nevertheless, Mahayana stands on its own and is valid as a spiritual path and practice because the folks that wrote the Mahayana sutras down were realized persons. The source of these teachings are all realized beings-- ***their assumed historical settings are merely skillful means to instill faith in the teachings in those person's who need to crutch of historical literalism...***" In any case, the Mahayana sutras show signs of literary composition and gradual development that are simply absent in the Pali suttas, which shows signs of being handed down orally in the beginning and having more consistency etc.
And because Mahayana is such a diverse set of teachings developed over a thousand years, you can actually easily find a sutra to support a whole range of positions to your own liking. So if for example your understanding is that your true self is eternal and changeless awareness (and I know you're an eternalist lol), sure, you can also find doctrinal support easily in Mahayana Buddhism. You may even find that the early Tathagatagarbha teachings like the early Mahaparinirvana Sutra (Mahayana) may even seem more eternalist than Vedanta and is rather unapologetic about it. In that sutra, Nirvana is described as the true changeless self and distinct from the five passing aggregates. Which is in direct contradiction to the earlier Pali suttas (and Mahayana Prajnaparamita sutras etc) which held Nirvana to be empty of self.
But that is just one small part of the Mahayana basket of scriptures. Earlier than the Tathagatagarbha class of teachings we have the Prajnaparamita class of teachings, which are the emptiness teachings - all dharmas including Nirvana are taught to be empty and illusory, and as I quoted to you in the past from this class of teaching, "Nirvāṇa is an illusion. Even if there is anything greater than Nirvāṇa, that too will be only an illusion." ~ Aṣṭasāhasrikāprajñapāramitā Sutra
And in the later developments, such as Lankavatara Sutra, which is not particularly prajnaparamita, not particularly tathagatagarbha, not particularly yogacara - but since it is such a late sutra it is a synthesis of all the earlier developments - PP, TG, YC all included in one coherent scripture. This is the sutra that teaches sudden awakening and is said to be the only sutra brought into China by the 1st Zen/Ch'an Patriarch in China, Bodhidharma.
In this Lankavatara Sutra, it explains that the doctrine of Tathagatagarbha is simply a skillful, expedient means taught to non-Buddhists who fear the notion of emptiness and cling to notions of true self. Its aim is actually to lead them gradually towards understanding emptiness, non-arising etc expediently. It teaches that true Bodhisattvas must treat tathagatagarbha as ultimately not-self, and warn against falling into non-Buddhist views of an Atman. But of course this is not what is being explained in the Mahaparinirvana Sutra for example, which explains itself as being the final definitive teachings, etc. So there are always contradictions between sutras simply because they are written and developed by different people.
So all these mean very different things to different people, all depending on what they take to be provisional and what they take to be definitive.
The general consensus among the majority of Mahayana and particularly Vajrayana people is that they do not hold a rather substantialist understanding of Buddha-nature. In Vajrayana for example Buddha-nature is understood as the inseparability of clarity and emptiness. In other words, even though clarity is an aspect of nature of mind, or one of the natures/essence of mind (the other being emptiness), that clarity too is not reified in terms of a changeless substantial true self but is empty of any self or substantial real existence as well.
Vajrayana generally take the middle way teachings on emptiness to be definitive but at the same time talk about the clarity aspect or the inseparability of clarity and emptiness. There is strong influence of Nagarjuna's emptiness teachings in terms of view on the Vajrayana teachings as a whole even though in terms of practice they are more focused on tantric methodologies generally speaking (or there may be practice-based teachings that claim themselves to be beyond tantras like Dzogchen and Mahamudra for example).
On the other hand there are also those minority like the Jonangs and the more extreme version of Shentong that takes some of the Tathagatagarbha teachings to be definitive and thus developed an eternalist doctrine out of it that is no different from the Vedanta teachings. The same goes for some adherents/teachers of Zen and Ch'an Buddhism which are also in many cases teaching stuff that are very much like Vedanta. At the same time you can find Zen teachers that teach a very non-substantialist understanding, and I especially like Dogen for example. So it is truly, a mixed bag, even within the specific traditions of Mahayana and Vajrayana. There can be no similar consensus among such a wide range of Buddhists on such issues.
But going back to topic, Mahayana and Vajrayana Buddhists generally agree with the Buddha's (the early/original teachings in pali suttas) description of Nirvana and generally do not hold substantialist views about it. However they do have different understandings of the details - and some Vajrayana people will talk about the difference of Bodhisattva's nirvana (non-abiding nirvana) versus the one-sided cessation of arahants and so on. All these I'll leave to the experts like Geoff who described it very nicely: http://dharmaconnectiongroup.blogspot.c ... dhism.html