Using a 3rd Generation ThinkPad X1 Yoga with 1440p display, the stylus calibration in default GNOME on Ubuntu 20.04 is erratic and unreliable. Trying to calibrate the stylus in the GNOME Settings Wacom section often results in the stylus being wildly miscalibrated (so the cursor is a quarter of screen away from the actual stylus).
I seem to eventually, after logging and logging out, switching between X11 and Wayland, and trying calibration several times to be able to get the stylus to recalibrate, but it's unclear what actually gets it to calibrate properly or why it so badly miscalibrates so often.