I have similar, but much worse, issues with my new iMac and magic trackpad. It was working great, but after upgrading it now jumps all over the place, making almost impossible to use
Bumping an old'ish thread after a search... The trackpad on my mid-2014 15" MBP has freaked out ever since updating to 11.2 (have also updated to supplemental 11.2.1 to no effect). Unresponsive; the curors will starts jumping around the screen with no input from me; won't accept gestures or clicks. After forced reboot, trackpad works for a few minutes, but inevitably freaks out again.
I ultimately ended up having to buy a cheap Logitech wireless (USB) mouse. If I try to use the trackpad, and unplug the mouse's USB receiver from my MBP, it'll work, again, for a few minutes, but then become unresponsive again, cursor will start jumping around the screen, but as soon as I plug in the mouse USB receiver, the cursor stops dead in its tracks, and accepts input from the mouse. 🤷♂️
I dunno... I know this is an old machine, but weird how it just started doing this immediately after updating to 11.2.
***I had ZERO issues when using 11.1 (I clean installed to 11.1 coming from Catalina, skipped 11.0)***