There are a lot of media platforms for studio productions such as Entertainment Tonight and Access Hollywood. Indie filmmakers need their own platform for PR.
And each of those platforms has millions of dollars of PR behind it to get it in front of the audience. The missing part isn't the platform, it's the PR. Good PR takes time and experience - you can either put in the time and get the experience, or you can spend money to hire people who've already done so. Youtube or Vimeo will work just fine as platforms as long as you have the PR to promote your work.
Youtube is for cat videos. I really like Vimeo.
I really like Vimeo too, but I disagree about Youtube. As a platform, it actually has some tools to help you do the necessary PR to get your video in front of the people who will be interested - Vimeo, unfortunately, doesn't.
For instance, out of about 20 short films on our Youtube channel our most-viewed one has over 40,000 views. The next closest one is at about 4,500. Our average is about 500. On Vimeo our top few films have about 2,500 views each.
The difference with the most popular one is that I ran a Youtube promoted videos campaign on it as a test last year - that's only the most basic, simple form of PR but it dramatically increased our viewership on that film. Even after stopping the campaign it's resulted in us sustaining about 1,000 views per month, 3-4x what we were getting over the previous year. Thanks to the campaign, if you search for some of the terms related to the film's subject on youtube our fim shows up in the first page of results.
Now that was a one-off film and a simple experiment, and I spent about $250 on the campaign in total. At the point I stopped the campaign views on that film had climbed to 9,000 per month. If the film were part of a series I'm confident that would have translated into even more views because people who liked the film would be more likely to watch the next one, and so on, making it even more cost effective. It was clear to me that with a coordinated release of a series of videos, and an advertising budget of maybe $1000, I could build a viewership in the hundreds of thousands.
The other trend I've noticed is that our documentary work gets a lot more views organically than narrative. That's because people aren't searching for generic things like "action movie" or "sci-fi" - and even when they do there are too many matches for you to stand out in the crowd. That doesn't mean a narrative film can't work on youtube, it just means it has to relate to a specific topic that people might be searching for - and that topic is the thing you need to focus your promoted campaign on.