I think it’s basically recalcitrance. Same as they suddenly turn into the world’s worst devs every time they have to make software for Windows. Apple hates mouses, but many people won’t consider not using one, so they reluctantly make an expensive, pretty, and absolutely terrible mouse to get you over the hump of the macOS switch then keep pushing you along to where they really want you: the giant touchpad, where they do have a moat, and which trains you for the rest of their ecosystem. They even sneak half of that touchpad into the mouse itself, and half of the mouse out, so the transition is oh so easy.

I have been a desktop trackpad user for so long now, I literally don’t want to use a mouse for anything except playing video games. The amount of flexibility offered by a good trackpad just wins most of the time as it is plenty accurate for quickly jumping around on one axis.

With a large enough trackpad, you could even move to a 1:1 type of movement, or add that functionality to a layer for the best of both worlds (like gyro enhanced aiming in games).