Got a new X1 Yoga recently. I installed a fresh ubuntu 18.04 and everything is working almost perfect (except suspend does not work every time). But trackpoint is a big headache to me. I am used to trackpoint (a long-time thinkpad fan going through X61 and X230) and the erratic behavior of trackpoint is a major disappointment to me.
Long story short, the solution by this post kind of fixed the problem.
device='TPPS/2 Elan TrackPoint' xinput set-prop "$device" 'libinput Accel Profile Enabled' {0, 1} # Switch acceleration profile xinput set-prop "$device" 'libinput Accel Speed' 0.5 # Increase sensitivity