This whole thing is horrifying, but the last paragraph is especially disturbing:
Since Herrera himself has a young daughter, and since there are "six children living within his fourplex alone" on Joint Base Elmendorf-Richardson, the government has asked a judge not to release Herrera on bail before his trial.
Even more disturbing is it said he was also producing content.
The Ars article seems to suggest that they were able to crack his phones pretty easily, which is a bit scary. I don't see anything about a computer.
Although it doesn't appear he was actually using any encryption apps to store material; rather, he used a fake calculator app as password protection. Obviously not the brightest bulb in the drawer.
It seems irrelevant whether this person is using encrypted channels if they failed to maintain anonymity. If they distributed material and leaked any identifying info (e.g. IP address), then it would be trivial for investigators or CIs to track them down.