I’m guessing the 10th gen is the one with the super long support lifetime or something like that? That’s a slightly weird iPad-ism.
In the most recent iteration of this lineup, the 12-inch MacBook was comically underpowered, especially for its price, there was no good reason to purchase that instead of an Air or a Pro. This was also quite short-lived, with an official discontinuation after four years.
It always made sense to me, at least: “pro” is premium in a power direction, “air” is premium in a lightness direction, and the base model is just the base model.
But I guess it is unsurprising that Apple doesn’t want to do a base model, haha.
Another way of looking at it, I guess, is just that it is an evolutionary process, and every MacBook is a descendent of the Air now.
Personally, I like my mini being a mid-tier device. Apple probably positioned it this way to avoid undercutting their cheapest model. It’s also a bit cramped. You’re sacrificing some usability for size and they’d rather people make that trade off because they want it rather than it being cheaper.