20 TB worth of content in the first place should easily be able to afford a backup system for it. He did come into that 20TB of content by legitimate means, right? You can't legally transfer a digital copy of a Blu-ray disc to HDD, so it must be UltraViolet copies, so he must have the original Blu-ray discs...
I recall a lawsuit that the RIAA brought against someone several years ago in which the defendant used an interesting argument to defend his having tons of illegally acquired music files on his computer/iPod. I may have some of the details wrong, but the argument was essentially that since songs cost $.99 each on iTunes, and an iPOD (at the time) could hold 8GB (or was it 16GB) equivalent to >$20K worth of music that no one in their right mind would ever pay for music to fill up an iPod. Therefore, Apple was encouraging people to get music illegally by providing a device to keep and play more of it that any sane person would ever buy.
I don't think the guy won with that argument, but it does make one think about the huge HDD capacities that are available for very low cost. What would people ever have to keep that takes 3TB (a single HDD), if not a bunch of movies, TV, etc., the majority of which has been acquired illegally? I'd bet the number of people who could legitimately fill that sort of space (home movies?), let alone 20TB, is very small.