Do you read that as Beckett saying that he is writing not from “nothingness” in an existential sense but from “a place without intellect or the observation that could declare something to be ‘nothing’ or ‘something’”? That latter seems likely.
I’m not sure if I quite understand your question (and this uncertainty of mine might very well stem from my own unfinished thinking on the subject …), but here is what I want to say for now:
On one level, as seen in the previous cited interview, Beckett seems to want to distance his writing from strict (restrictive & limiting) philosophical readings. By appealing to feelings he is suggesting some kind of subjective enigma in the centre of his own writing.
But we all know that Beckett read a lot of philosophy. And also; that a lot of his writing is in direct (and/or indirect) dialogue with previous thinkers and writers. Sometimes mocking, sometimes more as a way of trying out philosophical statements and positions in a literary universe.
Still, the previous decades of Beckett-research have been very theory driven. And maybe, in fear of becoming personal (doing soft-science), researchers have forgotten to investigate the more emotional aspects of his art. For example: is nothing an idea or a feeling in Beckett’s literature. And if we can agree that it is both, what more can be said about the emotional source of nothingness? How is it written out – in praxis – so to speak, and what can it tell us about … ourselves?