Yes I can understand that but by any practical purpose all the plugs I used around the world should be more or less equally safe, with unnoticeable differences.

Yes I can understand that but by any practical purpose all the plugs I used around the world should be more or less equally safe, with unnoticeable differences. A truly dangerous plug design would have killed enough people to be discarded by now. We're using local optima and the cost to move to the global one, whichever it is, outweighs the benefit. I live in Italy and recently the number of appliances sold with a German plug increased. I guess it costs less for the manufacturer to sell the same plug everywhere. They are offloading the costs to customers because not all sockets in my home accept that plug. Some of them are not multi standard, even the high Ampere ones. Eventually manufacturers could standardize plugs much more than regulations do.