Their argument rests on computation being a theory ("simulation") while agency/cognition being real ("processes"). Put that way, I don't buy the distinction.

Specifically, my reactions are:

a) Defining agency in terms "relevance" or "salience" is just circular logic.

b) Their argument about the extended Church-Turing-Deutsch thesis would already apply to physics and the universe, not just intelligent entities. So this is just poorly argued.

Also, I think Turing to his credit was somewhat aware of the issue, their own citation of Copeland 2020 mentions Turing's own musings on this.

But I'd love to understand more, this stuff is always neat to read about.