While 110V might be less of a shock risk compared to 230V, I have to wonder how much of a difference it actually makes in practice, like how much less likely are to die from the lower voltage?
Because on the other hand, the lower voltage increases the fire risk.
And by all means, if you have some high-risk area (storage rooms are quite common ones), do make special policy for it. But if you insist on the same policy for every area, you are actually endangering people.
The other limitations, particularly regarding space heaters and fans, usually come from fire insurance. Your premiums will be substantially lower if you prove your business gets regularly inspected for compliance and that electrical appliances get regularly checked if they are properly installed (i.e. no stacks of extension cords, no damage on the cable from chairs rolling over it or from floor tank lids).
In contrast, home fire insurance will often have priced in damages from such unsafe practices, and a no-pay clause for gross negligence - particularly the latter is what any reasonable business will be keen to avoid given the disastrous impact a fire can have.
Assuming that 10 dollar phone charger that Joe from Accounting got on Amazon or the airport store on the last vacation was not a dangerous counterfeit, that is. A sensible IT department will buy original chargers directly from the manufacturer or at the very least name brands such as Anker.
1. Putting appliances in random places (like your cubicle) can sometimes lead people to running extension cords to power these additional devices. And excessively long, or poor quality, or "excessively long, poor quality" extension cords can absolutely be a fire hazard. This is especially true when people don't understand "current carrying capacity" vis-a-vis wire gauge and choose the wrong cord for a given load.
2. Space heaters. If you include space heaters in your definition of "small appliance", then there is a fairly real risk. First, it's very easy for flammable materials to simply get too close to the heating elements of the heater, and catch fire. Second, space heaters tend to draw a LOT of current - typically more than can be handled by your generic power strip. And people don't understand this, and will happily plug a space heater into a power strip, which will then melt, short out, and catch fire.
On balance, the odds of having a fire caused by most small appliances in offices is still probably fairly low, but the risk is non-zero. And having a blanket ban, instead of trying to distinguish "well, your blender is OK, but the space heater has to go" is just the slightly lazier way to dealing with it.