Glad you figured it out. Definitely interesting, but it’s a well-known issue with drones, and it’s one of the reasons that public services are so freaked out about them even though the general public are not. Not just that they’re in the same frequency so as to disrupt many other devices: it’s that many of them transmit at a higher power than is legally allowed in the US
There are also some which can interfere with Z wave devices.
The DJI Mavic 2 is notorious for causing interference with other Devices as it has a particularly broad distribution pattern:
Probably the reason for that is that most drones that could take out your zigbee sensors would themselves be taken out by Wi-Fi in the buildings they were flying near. But yes, the drones themselves are a problem.
(And so, by the way, are the jammers that takeout the drones, in case one of your neighbors gets annoyed about your drone.)
As to why your Hue bridge was not affected, I could make some guesses, but they would only be guesses. It’s all about local interference patterns and architecture. And of course the individual channels being used.
As far as security systems, purpose built security systems use sensors on other frequencies (as, for example, does the SmartThings/ADT system), Or use channel hopping to improve signal consistency.
The standard smartthings hub is a very inexpensive home automation system. And it’s cloud-based. You get some additional convenience notifications if that’s of value to you, but it’s not a real security system and doesn’t meet those standards. If you follow the links on the SmartThings site to “security,“ as of this writing all of them will take you to the ADT model.
My own feeling is that within five years we will see licenses required for most drone sales as they are going to be an increasing problem. And so far the flyer community has not shown much interest in following either rules or guidelines. 