Mildred Marianne asked How do you define #IndieWeb? and a couple of us weighed in. My own brief answer concluded "More a state of mind than a thing, I'd say" but Chris Aldrich went into a lot more detail. His piece is well worth checking out in detail, as it offers a bird's eye view of all the different things the IndieWeb is and could be. I might take issue with singling out the country of America for his metaphor as being a tad parochial, but one could choose any reasonably democratic place instead.
I want to respond to a little thing. In questioning the closed nature of the big silos, Chris asks parenthetically: Would you use your phone to only call friends who use AT&T?

The simple answer for many people is yes. One reason why dual-SIM phones are popular, and why many people own two or more phones, at least in Italy (and probably many other places too), is that many carriers offer reduced rates to call other numbers on the same network. At least, that's the explanation friends have given me as they rummage through handbags looking for the specific phone that is ringing. I guess that with PAYG on a "free" phone, that approach makes sense. Or used to; it does not seem so prevalent these days. I don't know whether calls to the same network still get a discount. Possibly not. Either way, giving a discount to people on the same network is on a par with restricting converation to others in the silo.
As for Chris' final question -- What do you want the IndieWeb to be? -- that's something I sometimes struggle with myself. Part of me just wants to go back to simpler times, times when I first discovered NucleusCMS and bought this domain and another, almost 14 years ago.1 But the rest of me likes being able to write from my phone, to add photos, to have different kinds of posts, to respond from here when I choose, etc. etc.
In the end, the state of mind thing is what gives me most reward. As I work towards being more IndieWeb, which I also can't actually define, I'm forever learning new stuff, putting some of it to work, ignoring some, squirrelling some away for a rainy day.2 I still learn things via the big silos, but I've never learned anything in the process of actually using them.

It wasn't, actually, my first domain, which I may have got in 1997, but as I no longer own that it doesn't count. (The current owners could probably do with giving their site a little love. I have to think nobody actually visits.) ↩

Case in point: Chris offers a fragmention for any text I highlight on his site, but I choose not to use it. For me, copying the text will do. Others may choose to use the fragmention. That too is part of the IndieWeb. ↩