A better guess would be that the last new bitcoin will never be mined, because exponential growth in hardware dedicated to it will not last, given that the cost/benefit ratio (in terms of power, hardware, and effort) gets worse the fewer bitcoins you can mine per minute. And when people stop being able to mine them, their value will drop because people aren't making them anymore, which leads to it being even less worthwhile to mine them, until they are being mined too slowly even to hit the adjustment point - in other words, when the bubble pops, the currency will collapse completely.
So from that point of view, the last new bitcoin is likely to be mined earlier than expected - but it won't be the 21 millionth.
This is a very dangerous question. Thinking like this leads to huge security vulnerabilities in important systems. A better question is "What is the worst thing that could possibly happen if this system were successfully attacked?" If the answer is anything bad, it is probably best to assume someone will try to attack it.
As for the second part of the question, are we talking about the same internet? Because the one I'm on appears to be full of technically savvy people with loads of free time.
The problem with this is that then there is no institutional memory. Many student groups in colleges (at least at my college) fight the same problems in a recurring cycle every 4 years, because no one remembers why it didn't work out last time - the groups that avoid this are the ones that maintain connections with alumni or have a stable mentor. And this is for small groups that know each other well. If you had a corporation with 100s of people, it couldn't hold itself together with 25-30% annual employee turnover.
This articles mentality only really works if you are being hired to do a specific project, as an independent contractor, in the context of a larger team. Its also better for young people whose skill set is changing rapidly and may become better suited to different positions more quickly, as opposed to someone who has years of domain expertise and needs stability.
This is why you typically want to publish things like this as far and wide as possible - if any single source is compromised, it can be detected by noticing a discrepancy between two publicly available addresses. I'd wager they'll put it in their print edition (same as their physical address and phone number) from now on, because the NSA probably isn't going to everyone's house swapping out their magazines for altered ones, so anyone who gets the magazine will have a hard copy of the address.
Because the internet facing machine could have been infected with malware that allows someone to read the decrypted message, and send it back over the internet.
First, being compromised in the first place is less likely for the machine not connected to the internet, because it is booted fresh from a CD-ROM every time, and the CD is read only, so in order to install something unwanted on the computer the attacker would have to physically replace the CD.
Second, even if it were compromised, it is not connected to the internet, so there should not be any way for it to transmit the information, again unless someone has physically bugged the machine.
Does anyone else find it strange that the page containing this video also has a "send anonymous tip" link, which claims "we don't track anything, not even your ip address."
And of course the headline "modern media is often wrong, vapid, and easy to manipulate" is a little more sensational (and click generating) than, say, "Ryan Holiday claims some media outlets have biased incentives"
Which leads me to the amusing possibility that Ryan Holiday did not actually do those things, but is manipulating the media into thinking he did, which of course would prove his point.
So from that point of view, the last new bitcoin is likely to be mined earlier than expected - but it won't be the 21 millionth.