Frankly, provided you have error checking logic and don't store them next to a magnet... floppy disks are pretty damn bulletproof. I've had way more issues per-use reading a thumb drive or a CD/DVD-ROM than I ever did reading floppy disks.
Are they really that robust? Was I just storing them stupidly maybe? Or maybe it was because all the ones we had were used ones from work.
Of course, back then I knew enough to spend a bit more on the good quality ones, so that could have something to do with it.
Certainly 5.25" floppies from the late 80s and early 90s were nearly bulletproof in my experience. 1.2MB was a bit flakier than the 360KB though. All were still perfectly readable 20 years later, though at this point they all got thrown in the bin due to their obsolescence!
Not very. There's significant wear and tear from the drive head, to the point that you could see it with the naked eye after a while.
If you are not using them frequently, storing under ideal conditions, than maybe. I've been able to read floppies a decade after they were written. Not for long though. Drive required cleaning afterwards too.
CDRs are next level in terms of unreliability. Last year I discovered that almost none of the CDRs I'd burned in the early to mid noughties remain readable: simply had to destroy them.