Azalea trees normally generate anywhere on land, where there is a lush cave below it. However, on Java, it also generates on snow, powder snow, sand, red sand, and terracotta blocks, which Bedrock currently doesn't, causing them to not generate on snowy and hot biomes. This also applies to azalea roots.

Based on code analysis on the features JSON file for the azalea tree, the may_grow_on list doesn't include those blocks, which caused the issue. The fix here is simply to include the following blocks in the list to generate correctly such as:
minecraft:snow
minecraft:powder_snow
minecraft:sand
minecraft:hardened_clay
minecraft:stained_hardened_clay