Technically the article about Firefox and Chromium is correct, but this is a strictly security perspective in the same vein as saying Google Play is more technically more secure than F-Droid. When viewed with a security and privacy perspective, Firefox is better, albeit falling behind Chrome a bit, simply because Google is pretty much dominant in the mobile web pages and pretty much sets the standard.
In the desktop browser, Chrome is not good, even security-wise, at least according to Steve Gibson (of Security Now!), especially with regards of how it handles site certificates
With regards to Android Security:
It does not implement rollback protection so an attacker can downgrade the OS to an old version and exploit already patched vulnerabilities.
If an attacker could gain possession of your phone and/or have access long enough, its pretty much over regardless of what OS you are using on your phone.
As for the Linux phones, it feels more like opinion than fact. Notice that the most “finished” of the Linux phone is the PinePhone and its pretty much a prototype of sorts and not yet ready for primetime. There is a reason why the first batch is codenamed “Braveheart”.
The microphone kill switch is useless since audio can still be gotten via the gyro sensors.
Assuming you can get a good signal to noise ratio with that, this kind of approach to hacking is along the threat level of being hunted by APTs. All known devices will fall to them, given time.
All in all, the user reads like it is written with a one-sided mindset. It is not fake news, per se, more like propaganda. Notice how the site doesnt have bad things to say about Microsoft or Google, the worse offenders of privacy and security.