I'm all for the Venture Capitalism comparison, but I think you're numbers are quite a bit padded and just looking for the shock value, hopeless romantic upvote.
I agree the markets that Steemit is aiming to take market share from are enormous and highly competitive. Even, then, your price targets sound crazy.
Take a look at Airbnb's pitch deck or how back in 2011, bitcoiners were doubting that 1 BTC = $1000.
1 STEEM = $300 is a longshot, and it is kind of crazy. But all good opportunities are crazy.
By all means, come back to this post in 3 years and see what the value of steem is ;)