The problem is that SW uses file dates to determine whether mods need to be updated, and NMM uses File Date to set load order. So it's redownloading all of your mods every time you open the launcher regardless of whether or not they need updating.
What I do is unsubscribe from a mod immediately after it finishes downloading, and then resubscribing when it updates. That way I only ever download 1-2 mods on SW at a time.
THANK YOU. I generallt use the Nexus but felt like giving the Workshop a whirl and find it very annoying.
I've got two mods that I downloaded from the Workshop and I hate that aspect. If I decide to not use the mods and move them from my Data folder to a different folder that I've called UNUSED MODS it redownloads the mods. I find it incredibly annoying. I'll be unsubscribing them.
In relation to Steam Workshop, I downloaded the HD Texture packs but for some idiotic reason I can't use either of them without my game crashing even though my PC surpasses the requirements. If I move the two files to my Unused Mod folder it still downloads the textures. If there a way to stop that as well?