In case it helps, I've provided some substantiation for my position here: https://news.ycombinator.com/item?id=27334163

I should also clarify that I didn't intend to argue that lambda calculus should be the only way of understanding computation, but rather that it doesn't make sense to privilege the Turing machine model, as the comment I was replying to suggested.

The Turing machine model is arbitrary, and it is unmathematical in the sense I've described in my comment linked above. A different culture (or species!) would be likely to come up with a different computational machine-like model, but any culture that develops formal logics would be likely to discover the lambda calculus as a consequence of that.