Coming from the UK to Aus / NZ I was feeling smug ;) - but of course, this caught me out.

To be clear in the UK the wheel is on the right but the indicator is still on the left side of the wheel as in a European LHD car, just to keep things different.

Lohe this. Reminded me of the wild complexity in our global society

It's not a UK thing (which side the indicator stem is), it's a manufacturer thing.

Like position of reverse gear on a H-style gear stick, some left-and-up, some right-and-down; some with a collar interlock, some with a button, some you push the whole stick down towards the ground ...

And it's not always reversed! Australian-made and Japanese-made cars tend to have indicator on the right stalk, and wipers on the left. European cars tend to have indicators on the left stalk, and wipers on the right. But not always!

Case in point: my wife and I live in Australia (have done so all our lives), and my wife had a 2008 Ford Focus, made in South Africa (a RHD country). Indicator stalk was on the left, wiper on the right (aka "European" style). She then upgraded to a 2020 Ford Focus, made in Germany (it's the wagon model), and the wiper is on the left, indicator on the right. Which confuses me, as I drive a BMW, which has indicators on the left and wipers on the right.

Blinkers were always on the outside when most cars had manual transmissions, the opposite would be very inconvenient (and still is). Then somehow Britain didn't challenge the EU regulation that indicators must be on the left regardless of the driving side. Japanese and Korean cars still supply right-hand indicatored-cars to Japan, Australia and New Zealand, yet left-indicatored to the UK, go figure, European ones don't give a shit, so buyers of BMWs and MBs suffer (or enjoy?) being incompatible with the rest.

The indicator should be on the outside, so you can change gear (in a manual transmission car) and indicate at the same time. It's just common sense.

I am used to the indicators on the left though when driving my BMW, so I experience the classic "wipers instead of indicators" dance many times when I drive my wife's car. As most cars nowadays are automatics, I guess this reasoning is falling out of relevance more and more.

I also want to note that not all Australian built cars had wipers on the left and indicators on the right – many GM Holden models like the Kingswood and early Commodore models from the 1980s had them both on the one stalk – that stalk being on the right of course.