Apple just controls for the quality/experience they want to offer.

The various PC vendors have control over the hardware and software for the trackpads; they could make them good if they wanted to, or if they knew better. They just aren't "detail oriented" on a corporate scale.

I think it's something like 7 years since Apple's touchpads were made by Synaptics. They don't supply the touchpads in all Windows machines, though the non-Synaptics ones I've used are (in my judgement) consistently inferior.

(I worked at Synaptics until late 2006. It's possible that my information may be outdated.)

I don't think so. Over the last Х years I've tried using touchpads on Dell, Acer, Asus and other laptops (Apple's family included) with different hardware and software and came to a sad conclusion that there is no way I could use any laptop completely without a mouse, even though I try to avoid using it as much as I can even on a desktop. Touchpads feel like extremely slow and imprecise input method, a real distraction and obstacle in interaction with OS or app. So, I think that while something definitely may be in the drivers, there's another part in this problem where you have to decide which level of comfort do you agree to drop to when switching from a mouse to a touchpad/trackpad.