In the 1990's, an AI Corp developer (a woman friend of mine) completely automated the management of a large IBM mainframe using old fashioned AI. The computer worked in complete darkness. She called it "lights out computing".
This (presumably) refers to "Good ol' Fashioned AI" aka Symbolic AI (https://en.wikipedia.org/wiki/Symbolic_artificial_intelligen...) . It's a bit of an over-simplification to say it's a bunch of if statements, but it does involve encoding a bunch of rules/symbols by humans (as opposed to learning from data). It's a largely dead paradigm, though aspects of it are still found in various modern approaches (eg task and motion planning, knowledge bases, etc.) often in combination with learning approaches.
Having seen the code for a couple of "intelligent assistant" features: Yeah, basically a bunch of "if" statements. (The IA for the Apple Newton was a ton of special cases. It was clever, but certainly not 'intelligent').
Thus, the technology of AI has improved from a sea of spaghetti code that no human can understand, to a bunch of neural net weights that no human can understand. I love the march of progress. :-)