This is a chicken-and-egg problem. Until enough websites are using Indieweb standards to publish content, it will remain a niche.
This makes the Indieweb necessarily a fairly tech-centric space. However, I don't believe that this makes it less valuable. The Indieweb is a new technology, though it happens to be built on top of some very old ones. New technologies are always inhabited by tech types at the beginning.
I think it's not a problem for non-IndieWeb users to read IndieWeb pages though. Most often they won't even notice it's an IndieWeb site, when they come there by accident (e.g. a search or link from somewhere else).