The Warden can be angry at the player when bumping into them, however, mobs currently can't. This was changed on Java Edition recently but hasn't made it into Bedrock Edition so far.

How to Reproduce

1. Make a wall to contain the warden and other mobs
2. Spawn a warden
3. Spawn a couple of mobs, such as passive or hostile ones

Observed Result
The Warden only starts to get angry when the mobs walk.

Expected Result
The Warden starts to get angry as soon as it bumps into any mob.