Of course they are, same with undersea data centers (for different reasons).
But it doesn't matter. In the late-stage capitalism we find ourselves in, you don't need a real product, nor a promising prototype. You don't even need a good idea, you just need the promise that you'll come up with a good idea soon. That's enough to get the investors drooling, the shareholders hyped, and the gullible idiots engaged.
And you only have to maintain that long enough to pay yourself and your insiders some fat checks. Then when inevitably, reality barges in and people start to realize it was all bullshit and pipe dreams, you've already cashed out. If your PR team is good, the media and your sycophantic fans will praise you as a visionary who was simply, "ahead of their time." And you can go on to rip off more people.
It's basically Patreon scams but with billions of dollars.