Perhaps you are right and steemit is just a way of showing the world how this blockchain can work, so when the SMT’s arrive, the people will already have an idea about its implementations and features, similar to google and their nexus phones where they tried to show every other company how an android phone should be.
Maybe this blogging platform and its success is not the ultimate goal for the developers in the long term (prioritizing the adoption of SMT’s), but for now, we are here, building communities and trying to make this place worth a visit to people how aren’t yet on steem.
It would seem they have outright stated as much, so I certainly hope this is the plan.