Look, the facts are (for my hubs) I've got one over five thousand words, and at least two over four thousand words....
....there's also a ton of pictures, videos, links, ect - in those three hubs.
There's a lot of factors involving traffic...too many to list here, but the four and five thousand word hubs I've done haven't performed so well, and I'll never again create something that long on this website, and probably, any other website.
It's not worth it, and I don't think people online will actually read something that long.
I'm more successful with seven hundred to three thousand words.