Unless you've magically found a way to unlock a way to see all of the processes your phone does in the background they you have no way of ensuring that that phone or iPad is actually in airplane mode or what it is or isn't sending. Or if it's even off. Why do you think you can't take the battery out of any phone or device anymore. How convenient that he one true way to guarantee a device is sending nothing by removing the battery was eliminated as an option on every device made by every manufacturer all within the same 6 month period back around the end of 2015-2016. And iPhones have a particular vulnerability that androids don't. In guessing you never heard about the Pegasus software or The NSC Group. That's how they got Bezos back in '17. And I can promise you that his phone had a bit more than just run-of-the-mill security protocols. Bottom line is this: you have no clue what you're devices are doing inside the plastic shell. And if you think you can guarantee absolute data privacy by pushing one button that they left so easily accessible then you're their favorite kind of user. The clueless kind.
You can't take the battery out of most modern devices because they want to charge you to replace the battery, make the device itself disposable at which point they can charge you for a new one, and/or to make the device more attractive to consumer buyers (slimmer cases, tighter assembly tolerances, etc).
If you are that paranoid about what your device is/isn't sending when in airplane mode you can easily use a WiFi scanner to see if a device is still transmitting anything. For certain devices you can also completely disconnect the Wifi antenna internally or remove the Wifi circuit board altogether in devices such as laptops.
And yes, I am familiar with the Pegasus software and the
NSC NSO Group which is well known for their role in unlocking the Boston marathon bomber's cell phone when Apple refused as well as the recent iMessage Zero-Click vulnerabilty. And the particular vulnerability that the NSO Group used in that case was patched before it even became known to the general public that it existed.
At the end of the day you have two choices; put your tinfoil hat on and live under a rock or find a balance between security and sanity that makes sense to you; I personally chose to do the latter; so I use airplane mode, private browsing, Ghostery, Adblock, etc. while knowing none of it will completely eliminate the rampant intrusive data collection and privacy intrusions; but to me is it better than nothing....yes.
I was going to get my 107 but when they banned drones from filming the border crisis I said (Mod Removed Inappropriate Language)No!
I am curious as well why you chose to forgo the Part 107 process just due to the implementation of a no fly zone at the border. To me the two aren't related; you are going to eliminate your chances of legally accepting commercial drone work due to a move by the government that you disagree with? That's like refusing to get a driver's license until they will let you park on the White House lawn.