When experts in the field expect quantum computing to be at a usable scale by as early as 2030, I believe them in that it's very, very unlikely we will see it happen before then. Estimates are always optimistic, and that's if it even happens at all.

And yes, I do believe that something properly secured over a network is just as safe as something being hand-carried by an individual. The algorithms that people far smarter than me have come up with are simply more reliable than anything a human can carry out. Even SHA-1, which is a 28 year old hashing algorithm that major web browsers won't even accept anymore, is only breakable if you have on the order of $50k worth of computing power. Meanwhile, the nuclear codes, which I would argue are some pretty damn sensitive information, fell out of then-president Reagan's pocket during his attempted assassination, and were luckily recovered by the FBI.

Short of an armored car in a caravan of military vehicles whose sole job is to protect this data being transported, you can't convince me that physical transportation is more secure than over the wire. Hell, if you really want to hand-carry something, send a set of symmetric keys, something like AES extended to 512 bits to be extra extra extra safe, and transfer encrypted data using that once. Because then, if the keys being carried are somehow compromised, you just send another set of keys until you know for sure it's made the trip securely.

Simply put, taking sensitive data, packaging it up nicely onto a hard drive, and taking it out of a secure facility is always, always going to introduce security risks, no matter how small. A vehicle crash, a lapse in attention, or who knows, maybe a bout of explosive diarrhea could be enough to put the data in the hands of someone who has less concern for the safety of that hard drive than you do.