I think the average person does indeed care about privacy, otherwise we would use public bank accounts and would get rid of passwords, curtains and summer clothing.
Most likely, most people do not fully understand all implications of all technical details and aren't making fully informed decisions.
Ask someone how much they care that their bank details are known to the machines at Intuit when they setup their Mint account, or how much they care that random bank employees can see & manage their entire financial life when they call customer support or visit a teller.
Ask them how much they care that some machine somewhere in a Google datacenter is running an algorithm on every email they get.
In my experience, most people just want to keep parts of their lives private from people they know. They will upload nudes to iCloud and make jokes about FBI agents finding them.
You clearly don't understand Matrix. Dendrite introduces a hybrid-P2P model, ergo home servers become largely irrelevant, and portable identities become a thing.
Can Discord work offline P2P via Bluetooth LE? Nope.
I can only speak as I find it.