i think you have to take a closer look at what the app is doing before you can speak so strongly about what you think is happening.

anyways, i had to look into it to confirm that READ_PHONE_STATE is an encompassing permission used to check whether there are active phone calls happening. I could see any XMPP client needing this to be able to hold off connecting calls if there is an active call in place. This is the same permission that gives access to your phone number / IMEI - however, it doesn't automatically mean that the app is taking that stuff.

given that Conversations has been the leading XMPP client since forever and most XMPP clients are forked off of it, there are enough eyes on the codebase that something like this would stand out.

I'm not an Android developer, but from what i can see, the permissions nonsense probably stems from the way Google handles those permissions after Android 5.1 - I noticed that permission was added in 2.9.6 in F-Droid, which is one of the first to require Android 5.0 or newer. the older versions of Conversations that support A/V calling (after 2.8.0) do not have this permission, but they also only require 4.1

Version 2.9.6 - where that permission first appeared
https://web.archive.org/web/20210201223459/https://f-droid.org/en/packages/eu.siacs.conversations/

Version 2.8.1 - where audio/video calling was introduced
https://web.archive.org/web/20200509160527/https://f-droid.org/en/packages/eu.siacs.conversations/

READ_PHONE_STATE Permission, showing that its used to note the status of ongoing phone calls
https://developer.android.com/reference/android/Manifest.permission#READ_PHONE_STATE

i'll ask the XMPP group about it!