There is a bug with the new Azalea and flowering Azaleas in 1.17.

I've specifically noticed this with Villager pathfinding although it likely exists with other mobs. They seem to get "confused" around the Azaleas and their pathfinding ability is severely diminished. Sometimes they will simply stand still on/near Azaleas. 

I've had a Villager wander away from his home, unable to find his way back even though he was very close. I began to destroy the Azaleas in the surrounding areas and he immediately found his way back home.