All of the CO2 cylinder incidents I have seen, all involve incorrect use generally of beer gas CO2, usually large cylinders of 40-50Kg size. One, a cylinder was over 10 years old and had rusted inside burst whilst refilling, which considering they have their aged stamped on should never have happened. Other failures are "pub owners" attempting to refill CO2 cylinders themselves and pipes/tanks bursting. Quite a few incidents where "scrappies" unscrew the valve without emptying the cylinder first.
The CO2 used in fire extinguishers is dry CO2 and thus rust will never be seen in these cylinders, so valve jamming, single used worries is just a "wasted worry". Generally also, fire extinguishers are usually not worth the cost to refill and are just scrapped.
We have 17 CO2 extinguishers at work, which have fallen off the wall, been knocked over, ran into with trolleys and so far no one has died or asphyxiated or exploded !!!! Only another 2 years on their life before I might acquire them for fish tank use !!!
I wouldn't worry about FE safety at home, I am on my 34th cylinder (how many !!!) on my tank and no issues. They also work fine lying down, I stored mine in a magazine rack for years. We are using so little gas that the "wasted worry" of liquid CO2 getting into and freezing the regulator is really in practice a "wasted worry".
Biggest issue has always been leaks from low pressure side, like last night 1/2 way through watching a film noticed bubble counter was "going mad" and drop checker was blue. For some reason the JBL bubble counter had decided to start leaking at its O ring, so a film interlude of re-greasing, filing, fiddling, Ebay purchase to get working again.
Just use the fire extinguisher, might want to secure it, but not an issue, mainly so you don't damage the floor or rip your piping off if it falls over.
This is mine beside the tank. Been using like this for years. Have replumbed the CO2 piping since this picture so I can more easily get the FE out onto scales to weigh, see writing on the side of mine, so that when it is near having lost 2Kg weight you know to start watching carefully as getting empty.