[aikinai]

It's probably from people that switched to Macs back when there wasn't a single decent non-Apple trackpad and it was like jumping forward a decade in input experience. I assume there are some good non-Apple trackpads these days, but honestly wouldn't know for sure since I'm one of those people that switched back in the day and almost never use non-Macs now. So my default assumption will always be that non-Apple laptops all still come with tiny little non-responsive trackpads with bad texturing.

For the palm rejection, I almost never have erroneous inputs, and I think that's true for most people. And it's not that I don't physically mistouch; I realized how important and active the filtering is one time when I was doing something weird with my laptop that disabled palm rejection (maybe using my MacBook as a Bluetooth input for another computer?) and it was basically unusable from all the erroneous inputs.

[sublinear]

Some designs literally sidestep the problem by just moving the trackpad to the side instead of keeping it below the keyboard. The Logitech K400 is very cheap and has exactly the kind of small and trashy touchpad you speak of, yet I never have unintentional touches or clicks with it.