At every table I've played at, not broadcasting a Commlink or a Vehicle has been grounds for suspicion from the Police. And given that a significant amount of policing is done by relatively corrupt or aggressive organizations like Lone Star, it causes more trouble than it's worth. That's why we usually have the Decker Wrapper things for us (or, in the case of Commlinks get a cheap one to broadcast while our real one runs silent).
As to the whole License Plate thing, I find it very hard to believe that the equivalent of the License Plate is now some broadcast signal. Especially since you can still buy Morphic Plates.
With cars, I don't think Throwbacks would be too much of an issue. Sure, cops might use it as cause to harass someone, but I doubt a lack of Wireless would bring the world down on you. With Aircraft, however, I completely agree. Airspace has always been tightly regulated and in this dystopian world we all run in I'd be hard pressed to say that it's any less regulated (in fact, I'd insist it was more-so). Thus, if you're flying around without transmitting any data or filing flight plans (false or otherwise) then I'd expect you'd get a ton of attention once someone saw you. Then again, it's the seeing you part that'd be the tricky bit. Once they did, though? I'd expect instant contact, the aerial equivalent of pulling you over, and some mediocre to high profile harassment. After all, the poor and the average rarely have VTOLs to dink about in.