Materials Modeling had a Facebook group with nearly 2000 members that was supporting the proposal. Drones and Model Aircraft had a Youtuber with ~150,000 subscribers promoting the proposal, among other things. Operations Research had an outside forum looking to add structured Q&A. Cryptocurrency proposals invariably have a discussion forum.
Several Stack Exchange websites already allow identification questions:
You already mentioned story identification on Science Fiction & Fantasy, but Literature has this tag too
Species identification on Biology
Identifying things you can find in a garden
Identifying things you can find in the nature outside your garden
Identifying all kinds of ...