"code masturbation": getting pleasure out of making something only for yourself

I think primeagen sums it up well. At the end of the day, no one cares about the internals of a the product. They care that it actually works.

I'd caveat the statement that the only people who care about the internals, are the maintainers.

Just because the factory came about, didn't mean Bentley, Rolls Royce, and Bugatti stopped existing. Out of everyone who appreciates a car beyond making it go forward, there's still a slice of the population who will go out and look underneath the hood, admiring the intent and time spent handbuilding without any automation.