The ironic part is that those software description files are meaningless. AstraChat claims Advanced in all categories, but it's a proprietary commercial software, so nobody ran any kind of test suite to verify this.

That software list, how it's done and how it's ranked is literally confirming my initial point of critique :D

Last time I tried out several chat clients, most of them were alpha software, had lots of bugs appearing in normal conversation flows, well, or were so broken that they broke compatibility in subminor version updates to their very same client apps.

I just wish there was some kind of ACID test suite for XMPP or something else to reproducibly validate spec compliance. Maybe a test server or similar as a reference implementation. This way client or server maintainers would have to run their programs against the official test server to increase their compliance stats.