DeletedUser499 in signal after using burning sms for activation you can hide your number from search, and share username with contacts. ofc threemas approach to purchase license with crypto or cash and use without mobile number attached is better. and their servers are outside of 14 eyes aws, gcp, azere datacenters... and also it has passphrase encrypted storage, like molly, thought without notifications before unlock and less hardened (for example, no device–bound storage encryption, so adversary can brute force threema passphrase with gpu farm, to which molly is somewhat immune, due to secure chip entanglement + molly configured to make every passphrase guess longer, so attack is more expensive).
that saying I'm waiting for molly's selfhosting solution with option for BFU notifications, an, I hope, for threema-like user management) – that's perfect for personal use.