I think in essence the teachings are: All is what it is: Rupa is just rupa, Vedana is just Vedana. Sankhara is just sankhara. Sanna is just Sanna. Vinnana is just Vinnana, Nibbana is just Nibbana. Any other understanding or knowledge of it is distorted, deluded and will always be a kind of conceiving.
Delusional understanding is very normal teaches Buddha, i believe. Because seldomly, almost never, we understand things as they are. This is due to additions which arise from our disposition.
Our understanding becomes defiled with longstanding habits to see things as me, mine, my self, ugly, nice, attractive, repulsive, an escape, something that will make us happy etc. Almost all the time there is some judgement and attitude arising towards what is sensed, and at that moment there is much more then only sensing. That is not really pure. I feel that it can be understood immeditiately that any attitude or judgement is not a pure kind of understanding.
I think many people will easily understand that judgements like nice, attractive, ugly are not really characteristics of what is sensed, it is subjective. But that it is possible to sense and be without me and mine making is, i think, not easy to believe, let alone, to realise.
Thinking about oneself as a being is, ofcourse, conventional, like thinking about body and vinnana as me, but this does not mean that this is some ultimate or fixed Truth about oneself or an enlightend perspective.
In buddhism, also EBTs, always the difference between this conventional understanding and the understanding of the purified mind is always somehow assumed to be made and known by the readers, i believe, just like there is a mundane Path and supra mundane Path. The Buddha represents the ultimate understanding but often expressed himself in conventional ways. Sometimes, i feel, we get a glimpse of his deeper understanding such as in SN23.2