Inconsistency: Enderman is able to pick up flowering azalea, while unable to hold normal azalea bush.

The bug

While enderman can pick up flowering azalea leaves, it cannot hold normal azalea bush.

It's likely due to the change in 21w13a that flowering azalea is listed in small_flowers tag, which originally exists in enderman_holdable tag, being able to get picked up by enderman.