Azalea trees turn moss blocks they grow on into dirt, which is inconsistent for the following reasons:
1. While moss is in the dirt tag, it isn't meant to be actual dirt, all dirt blocks can be tilled into farmland and can lose their topping in one way or another (generally with a block placed above them), but moss cannot; therefore moss is only in the dirt tag for mechanical reasons;
2. Trees growing turn the block below them into grass; that also happens with nether fungi, turning nylium into netherrack; When a tree grows on moss, however, it doesn't turn the moss into dirt. Azaleas however are an exception, turning the moss into the rooted dirt variant; it seems that they check for the "dirt" tag, which makes them wrongly turn moss into rooted dirt.