A couple of results that I was convinced of, and then memorized without also memorizing the proofs:

A perfect computer would only need to do "work", in the entropic sense, when it deletes information. Of course we're orders of magnitude away from these theological limits right now and computing today is very hot and very gross.

Reversible Computing is the ability to compute a function without actually deleting, or otherwise confusing the states of your program. In theory you could run the program backwards, deterministically, and return your input. Reversible computing could be implemented on a theoretical "cold" computing substrate to not require any loss of energy.

One fundamental problem with the schema this author decides is how to separate the running of the program from it's output. Essentially this has wired the cpu % load to stdout. Naively, you'll start to leak output in arbitrary programs. You could be clever and specifically cap "computation" below 50% and output above it, but then I'd argue that you're just using your CPU as an output device.