In my post about waking my #Librem5 by calling to receive matrix messages I forgot to mention one of the actors: #PhoshAntiSpam.
PhoshAntiSpam rejects or silences incoming calls depending on a text file containing phone numbers and/or your address book.
If you're using #Phosh on your mobile phone and you get calls you do not want, it'll be of great help. Shoutout to @kop316@fosstodon.org