Seems like an interesting effort. A developer is building an alternative Java-based backend to Lemmy’s Rust-based one, with the goal of building in a handful of different features. The dev is looking at using this compatibility to migrate their instance over to the new platform, while allowing the community to use their apps of choice.
Then hashtags would have the same use as post tags on Reddit. I think thats a cleaner solution and there are plans to implement it.
Lemmy is already a very complicated project, and adding more functionality will only make it harder to maintain. Also there are lots of people who use wikis without Reddit, Wikipedia is one of the biggest websites in the world after all. So a Fediverse alternative is very much needed. Plus Lemmy and Ibis can federate in the future.