[wpm]

These devices do have FCC approval. It is why I can't send a garage door opener signal from my Flipper on the 315MHz band, because in the US, that isn't spectrum allocated to my fucking-about. I get a little message when I click send that says so.

All devices can be modified after the fact. Whether a manufacturer makes it easy, in the case of Flipper Zero, or hard, in the case of many other devices, to modify and install custom firmware that breaks FCC approvals, that lets it broadcast in frequencies it was not approved for, and allow the user to attack certain systems, is not really the manufacturers problem, anymore than Apple selling me a laptop I write malicious code on is Apple's fault, or the manufacturer of an IR blaster being responsible for me using it to mess with the TVs at the sports bar, or the Raspberry Pi Foundation for creating a device with a WiFi chipset that can be used to run deauth attacks, or the generic FM transmitter I could hardware hack to interfere with all sorts of stuff, or the RTL-SDR...or the ad infinitum

[Mountain_Skies]

Yes, in the early days of cell phones, it was easy to purchase a scanner from Radio Shack, cut a few resistors and then be able to listen in on phone calls. Radio Shack, the FCC, cell phone companies, and pretty much everyone else involved knew about this but it was allowed to continue because the scanners as sold were unable to eavesdrop, which was good enough for them to be legal.