Changes where there are plenty of chances to garner negative attention, but almost none to garner positive attention, and the ultimate success would be for the work to go completely un-noticed.
From an end user's perspective, they used to be able to Y in Z and it's stopped working, they google the problem and that's their first introduction to Wayland or Snap or Pipewire or Systemd or whatever.
One of the benefits to a traditional yearly product release cycle is to bundle such changes with a bunch of other, more obviously beneficial changes to sweeten the bitter medicine.