sneak’s pet issue is https://github.com/vector-im/element-web/issues/11655: that element web assumes that you want to log into the matrix.org homeserver by default unless you change its config to default to a different one.
I've user accounts on 3 different servers, run by 3 different groups.
Every single one of them has a configuration, despite a selfhosted instance, that phones home to centralized servers run by your for-profit company.
I'm not sure if this systemic problem is in your config files, your documentation, your defaults, your js client, or what. It's a failing of some part (or multiple parts) of the process.
The libremonde research is over 2 years old now, and the valid bits of it were addressed at the time (https://matrix.org/blog/2019/09/27/privacy-improvements-in-s...)