Too cynical. The author is one of the best experts on macOS (on the level of Jonathan Levin) and their utilities are geared towards understanding the OS, not so much as really doing something commercially viable

Dr Oakley is making his software for way too many years for such model to be feasible. Had he been relying for one of his apps to become a unicorn, he’d probably have gone broke by now.

The „business model” you are speculating about is second in its insanity only to making MIT-or-more-permissive open source software with an expectation that a multibillion corporation picking it up for its own use will share profits with the author in a sudden ethic attack.

This assumes too much and isn't really fair to.

Just check the website and you’ll know. The website is well respected in the Mac world and their utilities are free since forever

edit typos

People are allowed to be paid for their work and no one is forcing you to read the article.