The US is starting to come around in this regard (which is elaborated in the video I linked). Polarised NEMA 1-15 and 5-15 sockets are now the norm in new construction; with the neutral slot being slightly taller than line in both. It is therefore not possible to insert a polarised NEMA plug in the other way around.
The only difference between the two is that NEMA 1-15 has no ground while NEMA 5-15 does; a NEMA 1-15 plug will go into a NEMA 5-15 socket (but not the other way around). NEMA 1-15 sockets will still be common in situations that don't require a ground connection, such as sockets intended for class 2 equipment in bathrooms (like mains-powered shavers), but are now polarised, preventing line-neutral reversal when used in combination with a polarised plug.
However, there will be a significant lag time. Lots of devices are still sold with non-polarised plugs, for compatibility with both types of socket. Until non-polarised sockets go away, and electrical inspections enforce that all polarised sockets are wired correctly, and then devices are only sold with polarised plugs, appliance line/neutral reversal will still be a daily occurrence. This will take at least a couple more decades to be rid of.
There was an effort to standardise a polarised socket and plug specification for all of mainland Europe (IEC 60906-1), but this was shelved in the 1990s and abandoned in 2017 due to cost and waste concerns. IEC 60906-1 sockets appear to be unpolarised at first glance (for plugs lacking an earth pin); however, line and neutral are required to have shutters on them that only open with the insertion of a longer earth pin (just like UK BS1363 sockets), and thus you cannot insert a 2-pin plug into it in either orientation.
A lot of the rest of the world has only polarised plugs and sockets. This includes the UK, India, Malaysia, Brazil, Israel, China, and South Africa, which collectively make up just under 40% of the world's population. That list isn't exhaustive, but I can't be bothered looking up the socket standard in use by every country in the world and reading the specification for those standards to see if they permit unpolarised plugs :)
