This website contains age-restricted materials including nudity and explicit depictions of sexual activity.
By entering, you affirm that you are at least 18 years of age or the age of majority in the jurisdiction you are accessing the website from and you consent to viewing sexually explicit content.
Despite the media reports, the issue is not the journalist (I suspect he was invited on purpose to expose this).
The problem is that our highest level government officials use signal on their insecure private phones to discuss all kinds of security issues to avoid Federal Records Act and likely everything they discuss is available to foreign governments.
This explains it better: https://youtu.be/MERwAvesX9o