Since this is a home backup solution we're talking about I think most of the data COULD be lost without extreme consequences... and so all of it would fall into that "I could live without it but I'd really rather not."
Rule three: If it's 3 TB of video of the first year of your kid's life then edit it down to 5 minutes because that's all that anyone will watch (willingly) anyway.
Do you have kids? If so, then I'm curious as to whether or not you've ever gone back to watch old videos of your children from when they were just days, weeks, months or a few years old. You can't stop watching it. The emotions that come bubbling up are undeniable. You want to hang on to three terabytes of video of your kids for _your own sake_ - not anyone else. Do you not have kids? If not then I recommend you not open your mouth on topics you've got no experience on. To the rest of us (with experience) it just makes it obvious how ignorant you are on the subject and, due to association, casts everything else you say into doubt.
I bet that spacecraft will be seen by many politicians as profoundly dangerous.
And therefore, profitable.