They're certainly not a threat to Netflix, but they could conceivably fill a niche if they had some specialized content that people actually wanted to watch. Foreign language films, perhaps. Some smaller market that Netflix doesn't really care about.
It wouldn't make them the Future of Entertainment or anything like that, of course. But it might keep the lights on for a while.
The sooner they stop pretending that they're the leaders in 4K entertainment, the sooner people will calm down and rationally price the stock. No, Netflix doesn't need them, and no, neither does Sony or Amazon or Google, and no tweet or carefully timed pump can change that.
I don't think ultraflix could ever compete with the massive library that Netflix has unless they can manage to offer things that people actually want to watch.