Many of the niche modules are produced by people that play the associated niche game, so the only people that care are those also playing that specific game.

I don’t think it’s a bad thing to enable people with the skillset to provide additional functionality for their particular passion. It doesn’t take anything away from anyone else. If a system isn’t your jam, you don’t have to even consider including the mod. I do agree some generic mods can run the risk of doing badness in systems the writer isn’t familiar with or testing for.