I agree that the situation would be better with more sites, but it's pretty clear this is a special case for GOG (I don't think they'll start hosting just any mod), and even if it wasn't, this mod won't be on Nexus, so the total number of sources for it would stay the same.

I wonder why they don't also host the mod on Steam (like SKSE for the original Skyrim). Also kinda weird that the GOG employee they interviewed used this project as an example of how GOG is different from Steam, when Steam has a long history of hosting mods...