Interesting and optimistic predictions! I think the sign up process and learning curve to jump on Steemit is a huge hurdle for the majority of the population. I think photographers will come after the masses once they see it as a marketing platform to sell their work.
I think Steemit should adopt it's own marketing strategy with the slogan "Come for the money, stay for the community."
I also don't spread the word of Steemit on my other channels because of the reasons you mentioned. Too many people will come and see the challenges of getting started and dismiss the whole idea, never to return.
Yeah i should have written about the learning curve or simplification of the site goals for a beginner. It's true and that's why i've made a whole series of videos which I can give to my friends to help them as they get going. Even when sign up and communities start it will still be an issue. It was even an issue on FB and Gplus back in the days... but when there were more and more people the issue seemed to dissapear ... not because the site was all of a sudden easier to use... I just think there were so many people using it that answers were abundant. Also there was more incentive to figure it out.