I'm pretty sure it is illegal for airplane mode not to halt all transmissions.
Of course this won't matter.
I looked into my BIOS settings and apparently there is spread-spectrum modulation to reduce EMI? No idea if it reduces or masks side channel emissions. MAYBE THIS REQUIRES RESEARCH.
There are serious vulnerabilities, and everyone looks the other way. It is a great mystery.
Somehow there is demand for hardware random number generators when you could fit an antenna to the microphone jack and pick up low frequency cosmic background radiation. Or even higher frequencies, wifi requires error correction because of imperfections within the circuitry and echoes from walls requiring full knowledge of the device's placement and design.
In the end, the most amazing thing is that every purported benefit is really a hindrance, and real beneficial things without secret problems are ignored.
No really, look for every touted benefit that seems to provide marginal benefit over a simpler solution, and it is really an elaborate backdoor. x86 is designed for the unlikely scenario that a computer only needs a few dozen threads.
P.S. Buy iPhones, not Android, because the Apple tax is really the price for cybersecurity. In some mystery, carrier-specific forks of Android should really use a subset of apps, unique sprites, and unique bootloader screens. If Google cared about cybersecurity, they would bar outdated phones from being sold that can access Google Play. Android 4.4 devices are STILL BEING SOLD.
Ideally when people buy products, money goes towards a trust for long term maintenance of them. Like cemeteries. A properly designed product would be supported for a long time.
Purism's products seem to be from an irrational design basis that the GPL will cure everything.