Yeah... I'm synchronizing my off-site backup disks as I type this, and the file copies have been over a terabyte more than once now. Looks like the PC will be running still when I go to bed tonight.
For a mobile device, I'm not sure I would let that much data stack up unique to the device. Pictures/video I would try to do backups on a PC before it got to that. Never know when a phone might get lost/damaged after all. Contacts are already synced to remote service. Call logs/text messages are archived and sent away once a week, too.
I was going to mention that I have an SD card slot so I would just store that data on a removable card, but it's standard practice to have all storage encrypted on device nowadays so I can't just move it over.