I disagree. Gameplay loops come from programming in what it is a very simple and early game called: "The Game of Life" by John Conway.

The whole point of The Game of Life, is you are given an arena, a set of basic rules, and you may choose a starting position. The results will then vary and generate different experiences with your input. This is the interactivity of which you speak. The gameplay loop is how you interact with the program, it is the rule set.

The reason The Game of Life is useful as an example here is because it is a "zero-player" game, with no objectives, and yet is fulfills the basic tenets of what a game must have to be a 'game' or specifically what we think of as a "video game". You're not even competing against anything, you are simply interacting with the rule-set. The core gameplay loop is the rule-set, and the passage of time.

Games do not even necessarily need to be fun, but they have to cause some kind of human emotion. In this case, it's curiosity. And the level of detail within this simple rule-set that humans can input is shockingly large.

Even the earliest game that is known to exist has a similar function. The Royal Game of Ur it has 2 players competing against each other to get to the end of the board. It uses dice to add random chance for movement, and betting to add additional risk and reward. Despite this game emerging from the the earliest human civilization to ever exist as far as we are aware, once you have the rules, it is actually a quite entertaining and competitive game that combines both chance and strategy. Again, the basic rule set is the environment you are operating in, and the loop is each each iteration of positioning against your opponent.

You could create an AI that could follow some basic mathematical equation for what a good game should entail, but the entertainment value in the aesthetic and variations still need to come from humans.