TL;DR
New marketplace & Fab should hide “Unity only plugins” at default.
Description:
Unity already has its own marketplace and because there too many mobile developers in ecosystem, Unity related contents count too high. This cause overshadowing our ecosystem’s contents.
2D and 3D contents are okay because we can export them from respective engines and import to the other one. But plugins are not that simple. If we were talking about Godot, we could use integrated third party libraries or at least codes (I know that we need to convert Godot related functions and macros to Unreal equivalents). But for Unity and C#, this is not an option.
As an Unreal developer, I would like to see Unreal Engine plugins when I open new marketplace.
If I want to see “Unity only code plugins”, I can explicitly open them.