Guys, do you have any news?
I assume it's a platform bug. I have two laptops: t14 AMD with 4750U and elitebook 845 G9 with 6850U, both have the same problem. Also want to mention that t14 does not use i2c interface for touchpad, it works true i8042 so I think it's not a libinput problem.
I also mentioned that everything works good if both laptops works on a battery i.e. without power supply connected.