You seem to be very well versed in the technical aspects of blockchain tech. I must admit that this is not my area of specialty but that is precisely why your post caught my attention in the first place - you expressed your points of view in a manner that I could relate to, even if some points left me scratching my head! Much appreciated contribution - this is the quality content that Steemit should attract and strive to retain.

In regards to SBDs, I've written about the assumed peg extensively. I think there are many users that are unclear as to their branding. It's a predicament that needs to be addressed at some point, in my view, especially if adoption of the blockchain grows, as one would expect it to in the current environment.

As for my last point, I was curious as to whether you think that a future hard fork could potentially address some of the ensuing technical constraints that you anticipate as necessitating solutions for? Perhaps a hybrid of the current system of Witnesses as well as POS/sharding. I don't know if this is technically even possible with the blockchain in its current form, or whether it would require extensive rework. As you noted, probably not an immediate priority!

I do know that Witnesses collect "producer rewards" to varying degrees depending on their rank for maintaining the backend of the blockchain, so perhaps there could be some way for every day users to directly participate in that regard and alleviate their hardware burdens, aside from just voting for them. Just food for thought - again, not a technical expert, and just speaking from what I see other projects doing.