I've never had this issue with a bike, only on a car (well I have, TBH, but that was with a demo Yam GTS with HCS years ago, which I handed back to the dealer at the end of the ride). My car was afflicted with just the meerest ABS intervention, when right down to almost walking speed, sometimes. Really annoying, rather than dangerous in my case, but it would be a bit more worrying with only 2 wheels I guess.
We tried cleaning the reluctor ring windows, checked it was secure & running true & found plenty of debris from the sintered brake pad material around the face of the ABS sensor. We checked the sensor gap, the wheel bearings for wear/play, the wiring right back to the ECU, but just couldn't get the fault to clear. The messages looked OK when we scoped the sensor, but it is difficult to replicate real life road conditions without access to specialised gear. Anyway, the problem was only cleared by replacing the ABS sensor & wiring - the sensor must have been corrupted in some way, presumably by water or road/pad debris. Not the most scientific approach I know. In the OPs case though, working through the same process may help.
The only other generalised thoughts I had was with the relatively recent tyre change. Was the ABS sensor removed first & protected away from damage & only replaced once the whole wheel change was complete. Could the sensor wires have been pinched/trapped during the process. Were the wheel bearings checked for wear & the axle torqed up correctly, with any spacers in their correct places.
Good luck sorting this ....................... KEN