Adding lots of GPUs and CPUs doesn't make that not true. Those processing units still work by executing a series of instructions, they just do some fancy things with regards to the order of instructions and communication between units.
It may be more productive to think of things in terms of a more abstract, functional model of computing, but in the end, for anything to actually happen, that abstract model must be translated in to some series of instructions. I think that's what the quote was trying to get at.
It would be quite possible to design a processor that is not designed around series of instructions at all, but something more akin to functional programming. In this case, everything will “actually happen” without any kind of series of instructions.
Maybe my imagination isn't strong enough, but I don't see how a processor could work without being reducible to a series of instructions. The lowest level of "code" you give it might be more "functional", but there's a direct mapping between that and a sequence of states the processor goes through to actually do anything.
It may be more productive to think of things in terms of a more abstract, functional model of computing, but in the end, for anything to actually happen, that abstract model must be translated in to some series of instructions. I think that's what the quote was trying to get at.