My turn for a wall of text, sorry!

I do appreciate your preface, and I can certainly empathize with your frustration. Like you, I think that secure, private communications is generally a good thing and I am happy that there are awesome FOSS devs and groups devoting their time and skill to try and bring stuff like that to life. It is inspiring and I really do appreciate it. I, too, have had many a similar conversation :)

That said, I cannot disagree with your "it's not that hard" statement. At best it's well meaning but wrong, and at worst it is dismissive and counterproductive. Every change of any kind has a cost, as you pointed out (correctly): there is always some friction. When it comes to something that most non-tech enthusiast users view as pretty insignificant as messaging platform's privacy policies, any entrant is going to need to have a lot going for it to overcome the existing market inertia of the current players.

Honestly speaking, most people settled on their chat platforms of choice out of convenience a long time ago. Their friends used WhatsApp, so they hopped on. Meta bought them, but did that drive anyone away? Not really. They changed their privacy policy in ways that raised all sorts of alarm bells, but did it really change anything with their general user base? The fact that they still have somewhere between 2 and 3 billion people on the platform would seem to suggest it didn't have much, if any, effect either.

And it is important to highlight that that sort of inertia - a single platform being used by somewhere between a quarter and a third of every human being on this planet - is what needs to be overcome. Even Signal, arguably the current most mainstream FOSS app designed for private (though not anonymous) communication, which has been operating for around half a decade and has millions of dollars behind its development, has only managed to capture a measly 50 million or so users.

Then there's the reality that these standards keep changing which leads to new apps and protocols coming out. Again, I don't view this as a bad thing as a techie, but it could lead a reasonable user to ask: "why bother switching to this platform when I just switched to that other platform a year or two ago?".

I don't think the argument you are trying to make is that the overwhelming majority of people should be onboard with chasing after a new, more secure/private/anonymous/whatever platform every few years, but that's what it honestly amounts to at this point. No platform has everything, and even if something were written today that does have the everything of today, there's nothing to stop someone else from developing something new to entice people away yet again especially when you factor in profit motive to do stuff like that (case in point could be Meta's entering, and planned expansion within, the fediverse).

None of the above should be seen as arguments to accept the status quo or that people shouldn't be looking to move to something better. I wrote the above only to illustrate that moving platforms, especially for non-technical users, really is hard. It's frustrating for me because I, like you, would love to see users move to privacy-respecting and secure platforms. The reality, though, is that most people genuinely just don't care; nothing can make that more clear to me than WhatsApp. That is why having bridges (that wouldn't break native security and privacy features and wouldn't potentially get your account banned) would have been a gigantic feature that maybe could have enticed the average user. Unfortunately, that is not what the Matrix bridges do so I am left without a strong reason for even me, as a technical individual, to move off my current platforms.

Matrix doesn't provide better encryption than Signal (or even WhatsApp, ignoring the privacy side), it still requires trust someone just like Signal (your own paid, or someone else's, server vs Signal's servers), and even if I do adopt it I don't know that I would feel comfortable trying to convince the few members of my social groups to move as well given they are entrenched in their platforms and don't value the few additional benefits Matrix would seem to bring over something like Signal (which most of them didn't switch to, either).

I would love something like Matrix to "win" if it is as good as you say it is, but if its biggest (maybe only) selling point is privacy and security then I really don't think most users will move. Given Signal's security and seeming lack of a profit motive to sell my metadata, I am also ok (though not necessarily screaming with joy) with what they offer as well.

If you feel I missed or got anything wrong, I am open to hearing it! I feel we agree on way, way more than we do not.