I admire Signal and everything they do. Basically Software-as-Charity, for the greater cause. Now knowing this charity is actually millions drives me nuts. I hope the less expensive solution can be achieved in decentralization of the whole thing. Im sure it is possible to sustain it ourselves as a public service forever if everyone involved will have to pay with his personal computing resource - just like we are able to sustain decentralized finance now. And of course - the idea of a phone number as identity is very much flawed and unsustainable on itself, hopefully Signal team will be able to break through this problem as well