For a moment forget about the current downsides of preferring UK brakes living in a non-UK marketplace:
Is there any particular advantage to putting the front brake in the right hand?
Most people are right-handed, and having the more important brake in the better hand makes things a little easier. This isn't about strength but modulation; the front has more stopping power but needs finer control.
I find that a more important reason than the standard argument. That starts from the basis that signalling across the traffic - sticking your right arm out in the UK, left in most countries - is of particular importance. While doing so, you may need to brake one-handed (for example approaching a turn on a descent). If braking one-handed, it's better to use the back brake, as you really don't want to risk over-braking when the other hand isn't available for control or to stop you sliding forwards - slowing down hard isn't an option.
When riding an unfamiliar bike, the brakes take some getting used to even if they're on the same side as your normal. The problem comes when you either go straight into the sort of riding that requires optimal braking (e.g. a race, or technical MTB trails taken quickly), or when you're faced with the need to do an emergency stop.
For experienced riders: there's a huge advantage if you have learnt to ride UK style: you already know how to use them, and you don't need to re-train muscle memory (that is very hard).
For new riders: it's for me the kind of discussion where you can find theoretical advantages, that are in practice marginal and being in the mainstream is the better option (because it's a common basis you can rely on, and it's very likely that most bikes around you will comply to these expectations), even if sub-optimal in some use cases.
The advantage given by Chris H is good, and probably the reason of the mandate to this style of braking in the UK (which is good, because you have "a mainstream"). But on the other hand, you should always approach crossings carefully to start with, and you'd be probably safer by having the brakes at the position you expect them.
Moving from a country to another is however not the mainstream case, but in that case, if you already have the bike, you'll probably take it with you.
There's also a (small) inconvenient you didn't mention: getting spare parts. While calipers and levers are the same for UK and other countries, cable/hose length will differ, as a longer cable/hose will be sold with the rear brake.
People who also ride motorcycles generally prefer the front brake to be on the right (where it belongs in a motorcycle) and the rear brake to be on the left where the motorcycle has its clutch handle.
The important thing about the clutch is that you pull it quickly and then release it much slower.
The same reflex used with the front brake leads to hitting the road with your nose.
I have experienced:
But notably, not the situation you're describing :)
There's not much in it, for me. I think I have a mild preference for the European setup. Unlike everyone else who is worried about going over the bars while braking with their right hand, I'm more worried about not being able to brake hard enough with the left.
The main downside in the "wrong setup for the country" situation is that some bike mechanics get very uncomfortable with it. I had one who almost refused to return the bike until he'd "fixed" it.
It is not very unusual to raise a hand out handlebars to do something (drinking from the bottle, adjusting glasses or lights, pointing something out for a friend, scratching nose after the bug hit and more questionable activities that still happen, like holding a mobile phone), and for the most of the people this would be right hand, if done without thinking. On a bicycle like mine, left would stay on the front brake lever.
Now, if there is a sudden need of braking, hard-hitting the front brake alone may send you to the road over handlebars.
When the front brake is on the left, it may be better to use the hand on that side for random actions that for many people would be contra-intuitive and less convenient. Hence there is a benefit of having the rear brake on the left where the hand is more likely to stay on the handlebars.
I also agree that front brake has more power and needs finer control so using the right hand for it would be convenient for many. Likely this layout is more optimized for technical and focused riding.
