If you scroll down a bit, you'll see that sure enough this involved a switched-mode power supply, /probably some very cheap no-name/ [nope, missed that they included pictures of it]. Even though they're supposed to be at least minimally regulated under Title 47 part 15(B), in practice they're often a plague upon RF and as the article states sometimes the FCC has trouble mustering the energy for small spot trouble. While I feel more generous towards the FCC then some of the commentary I've seen on this, in that I don't think they've been remotely allocated the resources they should have to deal with this kind of small hotspot popping up since historically it was less an emergency matter, it's an issue (and a bit more surprising when it's a request from law enforcement, even if local).

I think it's a good reminder though that while modern wireless links represent a lot of fantastic engineering and are very valuable they can also be pretty fragile, and it's important to have a physical (be it digital or mechanical) fallback for critical tasks like authentication (in this case to access or startup a vehicle). There are situations where being surprisingly unable to operate ones vehicle (or access a building or whatever) could be quite serious, and the IoT ecosystem needs to give surprise interference some consideration as well. These sorts of incidents should also make society think about failure modes when it comes to interference, be it accidental or intentional. Law enforcement in particular should consider it from two sides, both in terms of emergency planning for if there was a major case (during an emergency or not), and as a strong note of caution vs some of the noises that have been made about LEOs themselves purposefully doing jamming during "periods of unrest" or the like. In an age of ever proliferating wireless devices, beware unintended consequences.

[Edit]: Thanks to Animats below for pointing out that it's UL approved Ventex, it's not in the article text but a photo is included at the bottom. So I guess that underlines SMPS quality control issues can be tough even with more attention paid, and shouldn't be taken for granted in planning even with part control. Though this also seems like it should make it something the FCC should give more attention in terms of confirming that this was a lemon and not an indicator of some more widespread problem. It should be easier for them to do that with a US-based operation.