These days, most folks posting here have a backup regime for their PCs.
I would hazard to guess that a lot of people reading this are very capable of creating a backup system, but they 'don't have the time' to either implement it or double-check that it's working.
A lot of smart people who deal in abstractions (like computing) are paralyzed. They have understanding how to do a task, but never seem to have the motivation to follow though. Especially if the task has no immediate reward, or no obvious indication that the task is done.
Going forward, I see Dropbox or something like it making "backups to additional local spindles" become quaint and anachronistic. Why backup to an external drive next to my computer, when "the cloud" arranges to have copies (and archives) of all my data on multiple machines I own, as well as on Dropbox's (aka Amazon's) servers?
However, considering how ridiculously easy it is to set up a simple rsync script, I doubt that many tech people do not do backups. Even though proper backups include frequent integrity checks, just setting up a rsync script gets you a long way already. If your data is encrypted though, a flipped bit might cause havoc already, thus making frequent backup integrity checks absolutely mandatory.
TL;DR I agree with the above.