Are you saying the individually dispensed medications are all sent to the pharmacy pre-filled?

This is what a box of Paracetamol (a pain killer and anti-inflammatory drug) looks like when you buy it at the pharmacy (this particular image seems to be from a different country, but they look similar).

That sounds wildly inefficient and inflexible in terms of transport/logistics/packaging tbh.

Well, yes. I get that point. It would save some deliveries to store 5kg of the drug at the pharmacy and have the containers separate. There are instances when they tell you they only have the 100-dose package on hand and need to have the 25-dose package delivered. That usually happens when you first start a long-time medication. The pharmacy will then deliver the medication to you for free (at least ours, I don’t know if that’s usual).

repercussions to filling a prescription wrong, especially if someone is injured

The trouble is, repercussions don’t help any injured person. And they require you to notice that you’ve taken the wrong medication. If you simply don’t feel better, your first instinct might not be “the drugs are wrong”.

There’s also usually a description on the printed label of what the pill should look like

We have that, to, but with a gut estimate of around 10,000 different drugs in circulation, that doesn’t really help with distinguishing them safely.