I like that there's no need for a centralised server & that you can self host at least 1 half of your DMs.
I like that they ask for no personally identifiable information from you. Migration between devices is by a data dump into an encrypted file.
I've been using it for 2 years & I have my family on it. They know I won't always be connected to the mobile network.
Voice calls have a delay sometimes but the quality is fine.
I've not seen a better alternative yet.
I'm very close to nuking telegram & signal.