Australian Stingless Bee “farming”: as the hobby is niche, even in Australia, there isn’t much publicly available advancement in hive designs, propogation methods and care techniques for native bees. This makes the barrier for entry high, and the chances of losing a hive when inexperienced is moderately high too. More people in the hobby would hopefully bring in more discussion and experimentation, and make the hobby more accessible to others by hopefully bringing the price of hives down.
TTRPGs/Wargaming outside of the big 2 games: if its not 40k or D&D, you are unlikely to find anyone that knows of alternate systems, let alone wants to play them. Makes it a lot harder to find a group outside of a game over discord or similar