Your issue is that you're misunderstanding the parent comment's claim. Izacus didn't claim that Windows laptop trackpads weren't bad -- the only claim made was that Apple trackpad drivers were worse. I've used a few friends' windows laptops, and while their trackpads certainly weren't good or perhaps even adequate (to borrow your term), they were without a doubt better than the Apple-laptop-running-windows combination, which I would classify as far below "adequate".
I have an X1 to test side by side with an rMBP running windows, and the X1 is categorically worse. Heck, I've tried many PC laptops (we have access to many at work) and haven't found anything that was as usable as an rMBP.
So, just name one laptop whose trackpad is better than an rMBP, I'll go try it side by side.