Re: Spot on
I don't think people value convenience or centralisation over privacy or security. The only thing people value is other people they want to talk to are on the same network and that happens by becoming a big name which requires money.
Signal is just as convenient to set up as WhatsApp, but most people choose WhatsApp because people they know use WhatsApp. WhatsApp wasn't secure before and it didn't matter, at the moment WhatsApp it is about as private and secure as Signal but that doesn't matter, and that might change again in the future and a few people might leave but not many.
Gmail is pretty inconvenient to use, but users put up with that because other people they know have a gmail address. It shouldn't make any difference as e-mail is an open protocol, but it does.
Countries could run their own decentralised operations, connect to the likes of Google via a individual pipeline but something like that just introduces more problems.
Open protocols and importing/exporting data. The only one that got there is e-mail. XMPP was sort of getting there but then Google pulled out when it had served their purpose.