This might be intentional, but it isn't stated anywhere in the changelog, so I decided to create this post after someone said it wasn't in the changelog.

The Bug
If a mob or player is close to a Warden when it sniffs 3 times in a row without colliding with it, the Warden will get angry at said mob or player.

Steps to Reproduce

1. Create a pretty big area. (I used a 7x7 area with a wool floor so I could run)
2. Summon a Warden in the 7x7 area
3. Go into survival.
4. Start playing Marko Polo, making sure to keep a good distance from the Warden after each sniff.
5. Notice how it doesn't get angry after 3 sniffs if you are far enough away.
6. Kill the Warden with /kill @e[type=minecraft:warden]
7. Place fences to divide your test area.
8. Summon a new warden on one side and any mob on the other side, making sure that the Warden and the mob are pretty close. (The player can also be that mob on the other side)
9. Wait for the Warden to sniff the player or any mob 3 times

Observed Result:
The Warden gets angry at the player or mob after 3 sniffs.

Expected Result:
The Warden will not get angry at the player or mob after 3 sniffs.