This is a good read and is definitely better than the current situation.
As it works now, no company will join since the risks are way too big. I am working on creating a company, and was exploring Steem as another way of distributing information and maybe make some way this way.
However I decided to just use it for personal reasons, it is currently too unreliable. As far as "spam" is concerned, the FAQ says the following:
Can I sell goods and services on Steemit?
Other than making a post and making sales manually, there is no interface for selling items directly on Steemit.com. You can list goods on the third-party website PeerHub.com. Through PeerHub, you can accept payment in Steem Dollars or STEEM, and you have the option to advertise your items through Steemit posts.
So, this means spam as such does not exist.
Another point I want to make, which everyone seems to ignore;
Even though most people join steemit for free, there are some that pay for an account. Also by adding posts or comments, you work to gain money.
Downvoting effectively steal this money from you. It could be said that the downvoter is showing fraudulent behavior, it's just a matter of time until someone starts a court case.
Also, some countries, e.g. Sweden, have very strict rules about censorship. Steemit is breaking these bigtime by allowing someone to grey-out their posts.
Keep up the good work, we need people fighting the good fight.