The Bug:
Sculk sensors are not activated upon shearing sheep, mushrooms, snow golems and pumpkins.
Steps to Reproduce:
Shear a sheep.
Shear a red or brown mooshroom.
Shear a snow golem.
Shear a pumpkin.
→ ❌ Notice how the sculk sensor does not activate upon doing any of these things.
Additional Information:
Quote from the 20w49a Changelog, "A vibration is anything that causes physical motion". I would definitely consider these as physical motions, as you are physically performing all of these this tasks.
Here I attached some videos, so you can visually watch the bug.
Note that some sculk vibrations are caused by my walking and the mobs' walking.