The other day, Time Machine on my system stopped, and it turns out that it has run out of space on my backup disk. Haven't had a chance to figure out how I'd like to proceed. Other than that, by far, Time Machine is the best backup tool I've encountered on any computer, and I've dealt with lots of them.
<knock on wood> Fortunately, I've never needed to see how TM does at restore though.
As for the OP , if the drive didn't have a hardware failure, then some recovery is likely possible. I've had a few drives over the years that failed, but would function for some period of time after being powered off for a while. In my experience, a catastrophic drive failure is not common, FWIW.