Most of the problems described here also apply to Matrix.

Also came up on Reddit: https://reddit.com/r/PrivacyGuides/comments/qkhqf7/xmpp_admi...

In matrix, not only can your homeserver usually impersonate you, but most information/history in rooms is considered public and archived forever. I haven't followed recently if there were mitigations on this topic, but that was historically one of the reasons many activists stuck with IRC/XMPP who support ephemeral discussions and/or an explicit data retention policies (eg. keep the latest 20 messages in this room so newcomers can have a little backlog).

In case that wasn't clear, in the XMPP model, the backlog for a room is kept on the room's server, not on every individual home server. In matrix, all data is replicated on all servers (which eats massive server resources, although newer implementations like conduit seem to improve on that) which greatly increases the possibilities for a bad actor to find their way to these conversations.

Basically all the issues listed in the article apply equally to Matrix, and most other communication platforms too.

There are some alternatives that overcome most of the issues with a "serverless" approach (hint: no practical communication protocol on the internet is ever truly serverless), such as Briar. However they generally have UI/UX and feature limitations that are impractical barriers to mass adoption.

If you're concerned that your communications may be specifically targeted, you should definitely consider carefully what solution meets your needs and security in the context of your threat model. Sometimes this might be self-hosting, or a pseudonymous XMPP account accessed via Tor, Signal or Matrix, or Briar, or something else.

What we need are good factual unbiased guides to inform people about the practical and security properties of various options. Unfortunately this article is not in that category.

If only Matrix had nice clients like Conversation or Gajim instead of all those mIRC and Discord look-alikes.

Those issue applies as well to the Matrix network since the global architecture is similar :)