There are peer to peer (or otherwise decentralised, e.g. multiple servers operated by many different people) alternatives to Signal. I haven't tried any of them, nor do I know which ones have been audited. But if the worst comes to the worst, there are alternatives that are hard to block.
In particular I remember reading about DeltaChat which piggiebacks on normal email infrastructure, making it really hard to block without massive collateral damage.
In particular I remember reading about DeltaChat which piggiebacks on normal email infrastructure, making it really hard to block without massive collateral damage.