You're 100% right on the expenditure bit. Video is basically the largest chunk of data on the Internet. It's also the most expensive to store and serve. One high quality video, is the equivalent of hundreds, if not thousands of blog posts with just text and photos.

The big bottleneck with DTube the IPFS server issue, so how do you store so much content, and serve it on-demand. Like you said, Google/YouTube have near infinite resources and just throw money at the problem. Lets wait and see.