I'd argue that settlement systems aren't a niche system and is something most of us use on a daily basis -- if not more frequently. Unless you're using cash for everything, every transaction you make goes through a settlement process, sometimes multiple times.

People often talk about how inefficient blockchain is, but they rarely have a grasp on how horribly inefficient our current settlement systems are. They are slow, expensive, inefficient, and complex.

I have doubts if it'll be widely used outside of the financial space, and I recognize that may be the context in which you were using the adjective "niche", but I do think it has the potential to be transformative within that space, and I think that space is potentially bigger than many of us realize.