I have a T431s and a T450s.
The T431s was a sort of "special edition" which I believe was the first to offer the "clickpad". And I agree, it sucks. However, the T450s was already back to a classic trackpad. It doesn't compare to the MBP trackpad (nothing does), but I have no issue with it. So it sounds like the 440 series was the only Thinkpad with that clickpad?
I would like a laptop that is perfect but, while I can easily imagine one, there does not exist a laptop that is perfect.
A perfect laptop for me would be a Macbook with LTE, ThinkPad keyboard, that would be serviceable by myself and that would not suck at running Docker.
I think the idea is as Lenovo not being IBM, they had to have ミ田 key and trackpad to get Windows license, while Apple is also praised of their huge clickpads, so the decision to integrate TrackPoint buttons and trackpad into single clickpad made sense on paper, except implementation sucked.
My T440 also has the "clickpad", and I hate it for the exact same reason you described. It's another example of the modern design trend toward form-over-function "overminimalism" (e.g. lack of ports, too much focus on thinness, etc.), in my opinion
Lenovo must have realized their screwup, because the later T-series editions went back to discrete mouse buttons.