Also, it's a tricky environment of disinformation generally, and in particular for anything valuable like Signal. If Signal is secure, attackers on privacy would want people to believe Signal is compromised and to use something else. If it's not, then they would want people to believe Signal is secure.

I think the solution is to completely ignore any potential disinfo source, especially random people on social media (including HN). It's hard to do when that's where the social center is - you have to exclude yourself. Restrict yourself to legitimate, trusted voices.