I like lemmy but also I’ve been following the drama from the sidelines, so I think the focus on Rust vs Java has nothing to do with the choice to create a lemmy alternative.
The reason sublinks exists is that the lemmy devs have made some large technical and PR mistakes that have led to multiple larger instance admins losing faith in them.
There was the Beehaw debacle where nutomic told the Beehaw admins that they should go to a different platform and take their “entitled” “demands” with them. It’s not surprising to see various alternatives to lemmy springing up as a result of the devs telling people to do so.
There was the illegal content spam incident which required instance admins to interact directly with the image database in complex ways for each image to remove the content from their servers, and I believe lemmy.world disabled submitting images if you are using a VPN or the tor network as a result. The lemmy devs have made some bafflingly derisive comments about that incident.
And then there’s the recent update that has broken federation of bigger instances, which is an ongoing issue. Communities are having to move instances to help with this bug which should have been caught in testing the update.
So sublinks seems to be some folks deciding that they can do it better.
Choosing Java is one way that they think they can do better. The argument goes, significantly more people know Java than Rust. Lemmy has had some problem getting extra help as a result of this limit, so hopefully sublinks will have a much larger pool of talented devs who will step up and submit code.
Sublinks isn’t the only one, too. Piefed is the python Lemmy alternative that’s cropped up recently and I believe there are some others in other languages.
Whether any of them can do it better remains to be seen, but it does seem like the Rust fans are struggling to understand that language choice isn’t always the most important part of a project.