First, I don't believe that we are an actual blockchain. I am merely using an analogy to describe how our pasts shape our present experience. We're obviously not machines.
I do agree that we may assume different characters depending on the situation. I couldn't say whether your online persona is closer to your real persona than other identities. What I could guess is that you may feel it is not necessary to put on a mask for your online presence. The same anonymity that gives some users freedom to become awful people online can also give us the freedom to be ourselves, if we choose.
By that same token, in other circumstances you might feel that your true self is inadequate for that circumstance, requiring a different persona, much like you might choose a wrench rather than a ratchet for a particular job.
In my case, I blog under my own name, so I don't benefit from anonymity. I've had circumstances in which my writing has resulted in real in-person interactions. I haven't felt any conflict in just being myself.