It's important to note that the term "influencer" only really has meaning within a specific context. That context cannot be as broad as "an entire platform," at least meaningfully, because the platform is the delivery mechanism. Once the scope expands to that level, you're not really talking about individuals that are influencing the community but instead people who are found by the community. The flow of power is actually inverted.
Once you look at context, you can talk meaningfully about people who influence that contextual community. If you were to, for example, ask about influencers on the Steem blockchain within the tabletop role-playing game community – I'm probably still one of those people along with maybe four others. If you talk about the contextual community of people who write about their travel experiences, there are probably another order of magnitude more people who can be considered influencers along with the entire community being an order of magnitude larger. The curve doesn't perfectly track, because the Dunbar number is real; people can only care about so many other people at any given time inside a given context.
For most of the interfaces which talk to the Steem blockchain as their backing database, it is unreasonable to ask the question "who are the influencers in this space?", not because there aren't individuals who, by nature of the people who comment and interact with them don't influence communities – but because the interfaces themselves don't support the construction and discovery of content for individuals to build communities. It is far more useful to talk about "interactives" on the Steem blockchain as it stands right now. Influence doesn't occur in an environment where discovery is difficult through the interface but there are people who act as local nexus of others who frequently interact and thus discover other creatives and sources of content.
Interestingly, discovering those people isn't so much an issue of talking to people as it is algorithmically demonstrable. In fact, doing so is one of the reasons that the other major social media platforms are as successful as they are. They concentrated on discovery and community self organization early on, which allowed people to coalesce around interactives and then self identified to external people who would be interested.
It is often said that the three most important things about real estate are "location, location, location" – and social media platforms are really just cognitive real estate. The location is how defined a given community can be, contextually, which separates it from its neighbors and other communities. Platforms which have strongly supported community separation and differentiation have done extremely well. There is more cognitive room, more territory, defined within the platform itself. Platforms which don't strongly support community separation find themselves in direct competition with other platforms which don't strongly support community separation and competing on strong network effect alone.
For social media platforms backed by the Steem blockchain, that cognitive spatial differentiation is something that they are going to have to work on to provide to the users in order to differentiate themselves. In the meantime, looking for influencers is applying the wrong mental construct if you're looking to understand growth patterns and potential within and across the platform. People need to be looking for others/accounts who act as interactives which facilitate other people meeting up.