1. Konami
I know No Man's Sky is going to win by a landslide, and it 100% deserves it, but Konami's brand of evil is just refinedly vile, while NMS's seems more pathetic, misguided and delusional. What tipped my hand was the recent news of them locking Kojima in a room for six months. I mean, damn.
Edit: I forgot about Mighty Number 9; it feels like it was released years ago, and I think that is because it was plain to me that it was going to be shit for years. Truly a lesson on how people manage to delude themselves when it comes to holding out hope; NMS's epic fail might have been relatively predictable, but MN9's disaster (and deception) were obvious long before release, yet people kept defending it to the end.
I also forgot about Palmer Luckey, but he's more tangentially related to videogames, and him being a shitty human being doesn't affect videogames all that much. In general terms of scumbaggery, of course, he's up there with Konami if not above.