I recently went down this rabbit hole and assumed the duplicated serial number in the EDID was playing a role in triggering it but even after switching to different monitors later on MacOS would still do this all the time. Just recently I moved my keyboard and mouse to the primary display that's connected over USB C and so far the problem has not reoccurred. No idea if having them on the secondary display was triggering the bug or if moving to the primary is just a way to mitigate it but FWIW, unless I've hit a string of good luck, it seems that for displays that also have USB combined MacOS takes the HIDs connected into account when deciding to flip your displays around every two seconds.