I wouldn’t run any BSD on a desktop (media hardware compatibility isn’t great), Kali should not be used as a primary OS (most people I know either dual-boot it or run it in a VM), and ReactOS is definitely not ready for everyday use (Linux+Wine has far better compatibility).
Manjaro has had a number of controversies too, which users ought to be aware of.
There are a lot of liberals and libertarians involved in FOSS, to the point where some FOSS and FOSS-adjacent media (ie ‘Slashdot’) is practically unreadable. Even the most (in)famous FOSS advocate, Richard Stallman, has appeared on Infowars and is reportedly a sex pest. But there are comrades involved in FOSS too, and there are obvious benefits from avoiding corpo lock-in and corpo spyware (what they call ‘telemetry’), so… there’s that.
The NSA’s BULLRUN program suggests that the TLS encryption is compromised anyway. My money is on certificate authories having given the NSA a backdoor ‘for national security’. I don’t think that they need to compromise an app directly.
If you need to communicate privately, please don’t use an open forum. Use an OS without telemetry (not Windows), make self-generated keys for GPG emails or OMEMO chat, and verify the key signatures directly with your comrades. If you need to communicate anonymously, bear in mind that there is no silver bullet.