I'm very sympathetic to this blog post, as it nicely describes why I use XMPP.
But, on a related note, I have noticed an interesting pattern where people talk past each other a little, especially when conflating user freedom and security.
If I'm to generalise, I feel the outlook of XMPP users tends to be more systemic and long-term. We've seen how chat networks come and go, we've seen the dangers of companies promising to serve your interests whilst also being a chokepoint of centralisation. So we tend to de-emphasize papercuts or current issues in clients and the protocol, on the basis that we have the power to fix them if we want to.
I feel that's shown in this blog post - all the points come back to the benefits of user freedom: no one entity controls you, the protocol serves you, you can choose your own clients, and if you don't like it, you can always switch / write your own!
What I've seen is that the people who gravitate towards Signal tend to be more concerned with the here and now - e.g. "how do I get my friend off telegram onto a secure / private service". I feel in many cases that making arguments about federation and the structure of the network won't sway them, as they'll always be able to point to some area where the clients are deficient in the here and now (depending on their interests - papercuts in the clients, different versions of OMEMO being used across the network etc).
I don't really have a solution to this, but I think all we can do is continue to make the clients and servers as good as they can possibly be. I always encourage anyone I manage to migrate to XMPP to send me any annoyances they find in the apps, so that they can eventually be fixed. We need to be ready for when Telegram, Signal, WhatsApp etc. abuse their power, because (as we've seen from the fediverse) that's the only time that "regular people" will care for the arguments that we're making about federation and user freedom.