Why is that so bad? Modders are just using Nexus as a way to host their mods and facilitate the community discussion. Some mods are huge after all, Nexus provides the hosting for the downloads, and software to manage them.
> The effect is that a lot of people wasted their time modding their game
Without a community site at the centre this process would be immeasurably harder. It's an inherently hard problem to manage hundreds of modders making independent mods and getting them all to work together. I'm not sure what the alternative is.
There are certainly reasons to not like Nexus, but I think you'd find modding somewhat requires a site like Nexus. You have to make both the consumer and the creator's experience easy enough that people will be bothered to do it. If I had to sift through 40 different personal blogs to download .zips of mods and load them, I just wouldn't bother.